Vulnerability Description
Vikunja before 2.6.0 contains an authentication bypass vulnerability in CalDAV BasicAuth endpoints that lack rate limiting protection. Remote unauthenticated attackers can issue unbounded credential-guessing requests against /dav, /.well-known, and /feeds routes to bypass the instance's anti-brute-force controls and compromise password-only accounts.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-m469-88xx-8rx2
- https://www.vulncheck.com/advisories/vikunja-before-2.6.0-authentication-bypass-
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-m469-88xx-8rx2
FAQ
What is CVE-2026-91973?
CVE-2026-91973 is a vulnerability with a CVSS score of 7.5 (HIGH). Vikunja before 2.6.0 contains an authentication bypass vulnerability in CalDAV BasicAuth endpoints that lack rate limiting protection. Remote unauthenticated attackers can issue unbounded credential-g...
How severe is CVE-2026-91973?
CVE-2026-91973 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-91973?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.