vulnerability / NVI-00013883 / Revision 2
Angular: SSR XSS via Unescaped Content Across DocumentFragment Boundaries in Fallback Raw-Content Elements
GitHub lists this reviewed advisory for @angular/platform-server, @angular/platform-server, @angular/platform-server, @angular/platform-server. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
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.
0.362%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.30122. 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.
@angular/platform-server
source listed>= 22.0.0, < 22.1.4
### Summary An XSS vulnerability exists in `@angular/platform-server` during server-side rendering (SSR) HTML serialization when traversing ancestor tags across `` element boundaries. When an application renders untrusted user input within raw-text tags (``, ``, ``), comments, or text nodes inside a `` that is nested within a fallback raw-content element (``, ``, ``, ``), matching closing tags (e.g., ``) are not escaped during HTML serialization. When rendered in a browser, this unescaped closing tag prematurely terminates the fallback container and executes trailing markup as active DOM elements. ### Technical Description In HTML5 parsing, fallback raw-content elements (``, ``, ``, ``) place the browser's tokenizer into `RAWTEXT` mode. In this mode, inner content is parsed as literal text until an end tag matching the container tag name (e.g., ``) is encountered. To prevent XSS breakout vectors during SSR serialization, the DOM serializer inspects a node's ancestors to escape any matching fallback closing tags (` `</tag`). However: 1
@angular/platform-server
source listed>= 21.0.0, < 21.2.22
### Summary An XSS vulnerability exists in `@angular/platform-server` during server-side rendering (SSR) HTML serialization when traversing ancestor tags across `` element boundaries. When an application renders untrusted user input within raw-text tags (``, ``, ``), comments, or text nodes inside a `` that is nested within a fallback raw-content element (``, ``, ``, ``), matching closing tags (e.g., ``) are not escaped during HTML serialization. When rendered in a browser, this unescaped closing tag prematurely terminates the fallback container and executes trailing markup as active DOM elements. ### Technical Description In HTML5 parsing, fallback raw-content elements (``, ``, ``, ``) place the browser's tokenizer into `RAWTEXT` mode. In this mode, inner content is parsed as literal text until an end tag matching the container tag name (e.g., ``) is encountered. To prevent XSS breakout vectors during SSR serialization, the DOM serializer inspects a node's ancestors to escape any matching fallback closing tags (` `</tag`). However: 1
@angular/platform-server
source listed>= 20.0.0, < 20.3.30
### Summary An XSS vulnerability exists in `@angular/platform-server` during server-side rendering (SSR) HTML serialization when traversing ancestor tags across `` element boundaries. When an application renders untrusted user input within raw-text tags (``, ``, ``), comments, or text nodes inside a `` that is nested within a fallback raw-content element (``, ``, ``, ``), matching closing tags (e.g., ``) are not escaped during HTML serialization. When rendered in a browser, this unescaped closing tag prematurely terminates the fallback container and executes trailing markup as active DOM elements. ### Technical Description In HTML5 parsing, fallback raw-content elements (``, ``, ``, ``) place the browser's tokenizer into `RAWTEXT` mode. In this mode, inner content is parsed as literal text until an end tag matching the container tag name (e.g., ``) is encountered. To prevent XSS breakout vectors during SSR serialization, the DOM serializer inspects a node's ancestors to escape any matching fallback closing tags (` `</tag`). However: 1
@angular/platform-server
source listed<= 19.2.25
### Summary An XSS vulnerability exists in `@angular/platform-server` during server-side rendering (SSR) HTML serialization when traversing ancestor tags across `` element boundaries. When an application renders untrusted user input within raw-text tags (``, ``, ``), comments, or text nodes inside a `` that is nested within a fallback raw-content element (``, ``, ``, ``), matching closing tags (e.g., ``) are not escaped during HTML serialization. When rendered in a browser, this unescaped closing tag prematurely terminates the fallback container and executes trailing markup as active DOM elements. ### Technical Description In HTML5 parsing, fallback raw-content elements (``, ``, ``, ``) place the browser's tokenizer into `RAWTEXT` mode. In this mode, inner content is parsed as literal text until an end tag matching the container tag name (e.g., ``) is encountered. To prevent XSS breakout vectors during SSR serialization, the DOM serializer inspects a node's ancestors to escape any matching fallback closing tags (` `</tag`). However: 1
03 / Response
What to do next
- 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.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-v3p8-whq6-r5jg ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
- CVE-2026-88060 ↗
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.
- Revision 2 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.