CVE-2026-27739
CriticalSummary
Angular SSR before versions 21.2.0-rc.1, 21.1.5, 20.3.17, and 19.2.21 has a Server-Side Request Forgery (SSRF) vulnerability in request handling. The framework trusts user-controlled Host and X-Forwarded-* headers without validation, allowing attackers to direct requests to internal resources.
Risk Assessment
The risk includes credential exfiltration, internal network probing, and confidentiality breach. The attack can be performed remotely without authentication.
Recommendation
Update Angular SSR to patched versions immediately. Additionally, restrict trust in Host and X-Forwarded-* headers and implement destination validation.
Original NVD description (English source)
The Angular SSR is a server-rise rendering tool for Angular applications. Versions prior to 21.2.0-rc.1, 21.1.5, 20.3.17, and 19.2.21 have a Server-Side Request Forgery (SSRF) vulnerability in the Angular SSR request handling pipeline. The vulnerability exists because Angular’s internal URL reconstruction logic directly trusts and consumes user-controlled HTTP headers specifically the Host and `X-Forwarded-*` family to determine the application's base origin without any validation of the destination domain. Specifically, the framework didn't have checks for the host domain, path and character sanitization, and port validation. This vulnerability manifests in two primary ways: implicit relative URL resolution and explicit manual construction. When successfully exploited, this vulnerability allows for arbitrary internal request steering. This can lead to credential exfiltration, internal network probing, and a confidentiality breach. In order to be vulnerable, the victim application must