CVE-2026-73563

Backstage is an open framework for building developer portals. Prior to 0.29.2, the experimental dynamic client registration and client ID metadata document features in the @backstage/plugin-auth-backend use full-string matcher.isMatch glob matching for...

CVE-2026-73563 Backstage: Unauthenticated OAuth account takeover via `redirect_uri` allowlist bypass in `@backstage/plugin-auth-backend`

Backstage is an open framework for building developer portals. Prior to 0.29.2, the experimental dynamic client registration and client ID metadata document features in the @backstage/plugin-auth-backend use full-string matcher.isMatch glob matching for...

CVE-2026-73563

Backstage CVE-2026-73563 affects the @backstage/plugin-auth-backend dynamic client registration and CIMD features. Before 0.29.2, full-string glob matching of auth.experimentalDynamicClientRegistration.allowedRedirectUriPatterns and auth.experimentalClientIdMetadataDocuments patterns allowed a ho...

Cross-Site Scripting vulnerability in @backstage/plugin-auth-backend

Impact This vulnerability allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other secrets from the user's browser. The default CSP does prevent this attack, but i...

CVE-2021-43776

Backstage is an open platform for building developer portals. In affected versions the auth-backend plugin allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other...

CVE-2021-43776 XSS vulnerability in @backstage/plugin-auth-backend

Backstage is an open platform for building developer portals. In affected versions the auth-backend plugin allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other...