CVE-2021-43776
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.
Does this matter?
Lower severity and a low EPSS score (0.66%). Track it; it rarely justifies an emergency change on its own.
Description
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`.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.66% probability · 49th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- linuxfoundation/auth backend
- Source
- security-advisories@github.com
References
- https://github.com/backstage/backstage/security/advisories/GHSA-w7fj-336r-vw49Third Party Advisory
- https://github.com/backstage/backstage/tree/master/plugins/auth-backendProduct, Third Party Advisory
- https://github.com/backstage/backstage/security/advisories/GHSA-w7fj-336r-vw49Third Party Advisory
- https://github.com/backstage/backstage/tree/master/plugins/auth-backendProduct, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.