{"id":"CVE-2026-50169","aliases":["GHSA-gv2q-mqqv-365m"],"title":"Angular Service Worker Policy-Bypass & Credential-Stripping Vulnerabilities","summary":"Angular Service Worker Policy-Bypass & Credential-Stripping Vulnerabilities","severity":"medium","cwe":["CWE-200","CWE-441","CWE-524"],"vendor":"angular","product":"@angular/service-worker","ecosystem":"npm","affected":["@angular/service-worker >= 22.0.0-next.0, < 22.0.0-rc.2","@angular/service-worker >= 20.0.0-next.0, < 20.3.22","@angular/service-worker >= 19.0.0-next.0, < 19.2.23","@angular/service-worker <= 18.2.14","@angular/service-worker >= 21.0.0-next.0, < 21.2.15"],"patched":["@angular/service-worker 22.0.0-rc.2","@angular/service-worker 20.3.22","@angular/service-worker 19.2.23","@angular/service-worker 21.2.15"],"published":"2026-06-15","updated":"2026-06-15","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-gv2q-mqqv-365m","references":[{"url":"https://github.com/angular/angular/security/advisories/GHSA-gv2q-mqqv-365m"},{"url":"https://github.com/angular/angular/pull/67494"},{"url":"https://github.com/advisories/GHSA-gv2q-mqqv-365m"}],"tags":["ghsa","npm"],"epss":0.00228,"epssPercentile":0.13788,"ingestedAt":"2026-07-07T15:41:58.958Z","slug":"CVE-2026-50169","body":"## Overview\n\nAn issue in the `@angular/service-worker` package compromises the integrity of request-policy enforcement during request reconstruction. When the Angular Service Worker intercepts network requests for matched assets, it reconstructs a new `Request` object using an internal helper function. \n\nDuring this reconstruction process, the helper function strips the strict, client-defined request redirect policy configuration (such as `redirect: 'error'`), falling back to the browser's default `'follow'` strategy.\n\nIf the target web application makes client-side requests with a strict policy (e.g., expecting a network error instead of automatically following redirects), the service worker will bypass this instruction and automatically follow HTTP 3xx redirects to other destinations. This acts as an unintended proxy/intermediary (\"Confused Deputy\") and can result in cookie/credential exposure or same-origin session-restricted data leakage if public dynamic routes redirect to sensitive routes.\n\n### Impact\nWeb applications registering the `@angular/service-worker` package are vulnerable to this redirect-policy bypass if they make safe client-side fetch calls (such as `{ redirect: 'error' }`) to paths matched by a service worker asset group (such as lazy-loaded JavaScript bundles or dynamic public assets) that can return HTTP redirects to authenticated same-origin secure endpoints. \n\nBy stripping developer-defined safety boundaries, the service worker allows the browser to transparently query and return data from credentials-guarded resources that should have been blocked at the network barrier.\n\n### Attack Preconditions\nTo successfully exploit this vulnerability, all of the following application states and parameters must concurrently exist:\n1. **Active Angular Service Worker:** The target application uses `@angular/service-worker` and has an active registration of `ngsw-worker.js` inside the client's browser context.\n2. **Asset Group Matching:** An `assetGroups` pattern in `ngsw-config.json` encompasses the target dynamic routing endpoint.\n3. **Same-Origin Dynamic Redirection:** The server routes a public matched asset route to a service that returns an HTTP 3xx redirect pointing to a sensitive, session-restricted same-origin private route (e.g., `/private/account-summary.json`).\n4. **Established User Session:** The victim user currently has an active authentication state, such as valid same-origin session cookies or auth headers stored by the browser.\n5. **Client-Side Safe Fetch Call:** The application initiates an explicit fetch request to the route with safety parameters: `{ redirect: 'error' }`.\n\n### Mitigations & Workarounds\nIf upgrading the `@angular/service-worker` package is not immediately feasible, developers should implement the following defensive measures:\n* **Avoid Public-to-Private Dynamic Redirection:** Refactor the server architecture so that public paths matched by service worker asset groups never issue HTTP 3xx redirects to authenticated same-origin secure endpoints.\n* **Strict Cookie Configuration:** Apply strict flags to session cookies (`SameSite=Strict; Secure; HttpOnly`) and consider explicit route isolations (such as subdomains) for credential-guarded private resources.\n* **Exclude Secure Endpoints from SW Config:** Verify your `ngsw-config.json` settings and ensure that patterns targeting dynamic, secure endpoints are explicitly excluded from automatic asset groups or caching scopes.\n\n### Patches\n- 22.0.0-rc.2\n- 21.2.15\n- 20.3.22\n- 19.2.23\n\n## Affected packages\n\n- `@angular/service-worker >= 22.0.0-next.0, < 22.0.0-rc.2`\n- `@angular/service-worker >= 20.0.0-next.0, < 20.3.22`\n- `@angular/service-worker >= 19.0.0-next.0, < 19.2.23`\n- `@angular/service-worker <= 18.2.14`\n- `@angular/service-worker >= 21.0.0-next.0, < 21.2.15`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `@angular/service-worker 22.0.0-rc.2`\n- `@angular/service-worker 20.3.22`\n- `@angular/service-worker 19.2.23`\n- `@angular/service-worker 21.2.15`","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":27.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}