CVE-2026-50168

An issue in the @angular/platform-server package allows remote attackers to bypass host allowlist constraints and direct server-side outgoing requests to arbitrary external endpoints. This occurs due to a parser differential between the strict WHATWG URL parser used for allowlist validation and the lenient Domino URL parser used to initialize the server emulated DOM.

When a server-side request contains a malformed URL with a double port structure (e.g., http://evil.com:80:80/path), Node's strict URL.canParse(url) logic returns false and skips host check validation entirely. However, the same malformed URL is later accepted and parsed leniently by Domino's internal parser, which resolves the origin to http://evil.com:80. The Angular SSR HTTP request interceptor (relativeUrlsTransformerInterceptorFn) then resolves all relative backend HTTP requests against this adopted origin, executing the SSRF attack.

Attack Preconditions

To successfully exploit this vulnerability, the following environment parameters and application states must all concurrently exist:

1. Active Server-Side Rendering (SSR): The application must be configured to run with Angular Server-Side Rendering (@angular/platform-server).
2. Host Header/URI Propagation: The SSR handler must reconstruct the request URL using raw client inputs (such as request Host headers or absolute-form URIs) and pass it as config.url to the rendering API (renderApplication or renderModule).
3. Outbound Relative HTTP Requests: The server application must perform outbound backend API requests using relative paths (e.g., this.http.get('/api/data')) that undergo base-URL interceptor rewriting.
4. Enabled Allowed Hosts Check: The server must use the framework-provided allowedHosts options to limit valid server locations.

Any Angular application utilizing server-side rendering (@angular/platform-server) that configures host routing allowlists (allowedHosts) is vulnerable to this allowlist bypass.

By sending an HTTP request with a malformed Host header (e.g. Host: evil.com:80:80) or an absolute-form request URI, an attacker can bypass the allowlist logic completely (even when configured with a strict default deny setup). The SSR application will then route all relative HttpClient outgoing API queries, which commonly carry sensitive credentials, session cookies, and internal authorization tokens, to the attacker-controlled server instead of the intended backend services. Additionally, the attacker can supply custom payloads back to the emulated DOM, leading to response injection and content poisoning within the rendered HTML served to users.

Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.

Kodem intelligence

• 22.0.0-rc.2
• 21.2.15
• 20.3.22
• 19.2.23

1. What is CVE-2026-50168? CVE-2026-50168 is a high-severity server-side request forgery (SSRF) vulnerability in @angular/platform-server (npm), affecting versions >= 22.0.0-next.0, < 22.0.0-rc.2. It is fixed in 22.0.0-rc.2, 20.3.22, 19.2.23, 21.2.15. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
2. Which versions of @angular/platform-server are affected by CVE-2026-50168? @angular/platform-server (npm) versions >= 22.0.0-next.0, < 22.0.0-rc.2 is affected.
3. Is there a fix for CVE-2026-50168? Yes. CVE-2026-50168 is fixed in 22.0.0-rc.2, 20.3.22, 19.2.23, 21.2.15. Upgrade to this version or later.
4. Is CVE-2026-50168 exploitable, and should I be worried? Whether CVE-2026-50168 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2026-50168 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2026-50168?
   • Upgrade @angular/platform-server to 22.0.0-rc.2 or later
   • Upgrade @angular/platform-server to 20.3.22 or later
   • Upgrade @angular/platform-server to 19.2.23 or later
   • Upgrade @angular/platform-server to 21.2.15 or later