By Null Ventures MCP platform
Menu

vulnerability / NVI-00002194 / Revision 2

PHP JWT Framework: JWSVerifier uses algorithm from unprotected header, enabling algorithm confusion attacks

GitHub lists this reviewed advisory for web-token/jwt-library, web-token/jwt-library, web-token/jwt-library, web-token/jwt-bundle, web-token/jwt-bundle. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.

source listedactiveGHSA-jc38-x7x8-2xc8

This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.

01 / Meaning

Why it matters

Published affected context helps an owner decide what evidence to gather. This report has not examined your application.

02 / Applicability

The affected context

Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.

web-token/jwt-library

source listed
  • < 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-library

source listed
  • >= 4.0.0, < 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-library

source listed
  • >= 4.1.0, < 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-bundle

source listed
  • < 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-bundle

source listed
  • >= 4.0.0, < 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-bundle

source listed
  • >= 4.1.0, < 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-experimental

source listed
  • < 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-experimental

source listed
  • >= 4.0.0, < 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-experimental

source listed
  • >= 4.1.0, < 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-framework

source listed
  • < 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-framework

source listed
  • >= 4.0.0, < 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-framework

source listed
  • >= 4.1.0, < 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database

web-token/jwt-library

source listed
  • ECOSYSTEM: introduced 0; fixed 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-library

source listed
  • ECOSYSTEM: introduced 4.0.0; fixed 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-library

source listed
  • ECOSYSTEM: introduced 4.1.0; fixed 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-bundle

source listed
  • ECOSYSTEM: introduced 0; fixed 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-bundle

source listed
  • ECOSYSTEM: introduced 4.0.0; fixed 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-bundle

source listed
  • ECOSYSTEM: introduced 4.1.0; fixed 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-experimental

source listed
  • ECOSYSTEM: introduced 0; fixed 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-experimental

source listed
  • ECOSYSTEM: introduced 4.0.0; fixed 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-experimental

source listed
  • ECOSYSTEM: introduced 4.1.0; fixed 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-framework

source listed
  • ECOSYSTEM: introduced 0; fixed 3.4.10

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-framework

source listed
  • ECOSYSTEM: introduced 4.0.0; fixed 4.0.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

web-token/jwt-framework

source listed
  • ECOSYSTEM: introduced 4.1.0; fixed 4.1.7

## Summary `JWSVerifier::getAlgorithm()` in `src/Library/Signature/JWSVerifier.php` (line 144) merges protected and unprotected headers using PHP's spread operator: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` In PHP, when spreading arrays with duplicate string keys, the **last array's values take precedence**. Since the unprotected header (`getHeader()`) is spread second, an attacker can override the integrity-protected `alg` parameter by placing a different value in the unprotected header. This creates a Time-of-Check/Time-of-Use (TOCTOU) vulnerability: 1. `HeaderCheckerManager` validates `alg` from the **protected** header 2. `JWSVerifier` uses `alg` from the **unprotected** header for actual verification The same issue exists in `JWEDecrypter.php` (lines 120-124) where `array_merge()` exhibits the same last-wins behavior for `alg` and `enc`. ## Affected Code **JWSVerifier.php line 144** — Spread operator merge order allows unprotected header to override `alg`: ```php $completeHeader = [...$signature->getProtectedHeader(), ...$signature->getHeader()]; ``` **JWEDecrypter.php lines 120-124** — `array_merge()` with same las

GitHub Advisory Database via OSV

03 / Response

What to do next

  1. investigate

    Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database

  2. vendor patch

    The original advisory lists fixed boundaries 3.4.10 for web-token/jwt-library. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  3. vendor patch

    The original advisory lists fixed boundaries 4.0.7 for web-token/jwt-library. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  4. vendor patch

    The original advisory lists fixed boundaries 4.1.7 for web-token/jwt-library. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  5. vendor patch

    The original advisory lists fixed boundaries 3.4.10 for web-token/jwt-bundle. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  6. vendor patch

    The original advisory lists fixed boundaries 4.0.7 for web-token/jwt-bundle. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  7. vendor patch

    The original advisory lists fixed boundaries 4.1.7 for web-token/jwt-bundle. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  8. vendor patch

    The original advisory lists fixed boundaries 3.4.10 for web-token/jwt-experimental. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  9. vendor patch

    The original advisory lists fixed boundaries 4.0.7 for web-token/jwt-experimental. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  10. vendor patch

    The original advisory lists fixed boundaries 4.1.7 for web-token/jwt-experimental. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  11. vendor patch

    The original advisory lists fixed boundaries 3.4.10 for web-token/jwt-framework. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  12. vendor patch

    The original advisory lists fixed boundaries 4.0.7 for web-token/jwt-framework. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

  13. vendor patch

    The original advisory lists fixed boundaries 4.1.7 for web-token/jwt-framework. Confirm the publisher’s latest guidance.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV

A fixed release is not deployment evidence.

Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.

04 / Limits

What this report cannot establish

  • Customer inventory, deployment, reachability and exploitation have not been inspected.
Read the collection and interpretation limits ↗

05 / Provenance

Sources you can inspect

Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.

  1. GHSA-jc38-x7x8-2xc8 ↗

    GitHub Advisory Database · vendor advisory

    Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.

  2. GHSA-jc38-x7x8-2xc8 ↗

    GitHub Advisory Database via OSV · vendor advisory

    Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.

Public revision history

Only published revisions appear here. Routine fetches do not create a material-change event.

  1. Revision 2 ·

    Source facts changed; compare the preserved prior revision.

  2. Revision 1 ·

    First indexed by Null; source disclosure date is shown separately.

Read the public revision data ↗

The next step is private

Bring the question into your environment.

The connected workflow is a development preview for inventory, contextual matching, owner decisions and evidence-based verification. No system-specific result is generated by this page.

See the synthetic workflow preview ↗