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vulnerability / NVI-00014162 / Revision 2

PraisonAI: Origin-validation bypass (startswith prefix match) enables unauthenticated cross-site request forgery against the PraisonAI MCP HTTP server

GitHub lists this reviewed advisory for PraisonAI. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.

source listedactiveGHSA-pvph-5j39-v8qcCVE-2026-55532

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.

CVSS

7.6 high

GitHub source severity; exploitability and local consequence require separate evidence.

As of · GitHub Advisory Database

EPSS

0.197%

FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.09531. Missing scores are unknown.

As of · FIRST EPSS

02 / Applicability

The affected context

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

PraisonAI

source listed
  • < 4.6.58

### Summary The PraisonAI MCP server exposes an HTTP-stream transport (praisonai mcp serve --transport http-stream) that binds to localhost and, by default, has no API key. Its only access control for browser-originated requests is an Origin allowlist, which the code implements as required by the MCP 2025-11-25 security guidance. The allowlist check uses a prefix match (request_origin.startswith(allowed)), so any Origin whose string begins with http://localhost or http://127.0.0.1 is accepted, for example http://localhost.attacker.com. An attacker who registers such a hostname and serves a page from it can, when a victim visits the page, issue cross-site requests that the MCP server accepts and executes without authentication. Because the request can be sent as a CORS "simple request" (Content-Type: text/plain, which the server still parses as JSON), it requires no preflight, and because tools/call does not require a session, a single forged request executes an MCP tool. This is a blind cross-site request forgery against a developer's local agent runtime. A natural end-to-end impact is persistent prompt injection: the forged request creates a rule file that the agent runtime loads

GitHub Advisory Database

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. FIRST EPSS

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-pvph-5j39-v8qc ↗

    GitHub Advisory Database · vendor advisory

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

  2. CVE-2026-55532 ↗

    FIRST EPSS · official catalog

    Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.

Public revision history

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

  1. Revision 2 ·

    Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.

  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 ↗