cvedb.io
CVE-2021-43776
HIGH · CVSS 7.4
EPSS exploitation probability: 0%
Published 2021-11-26T19:15:07.843 · Last modified 2026-06-17T04:11:23.687

Summary

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 secrets from the user's browser. The default CSP does prevent this attack, but it is expected that some deployments have these policies disabled due to incompatibilities. This is vulnerability is patched in version `0.4.9` of `@backstage/plugin-auth-backend`.

Affected products

linuxfoundation — auth_backend

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.