CVE-2026-91973
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.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.7
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- EPSS probability
- 0.61%
- CWE
- CWE-307
- Published
- 2026-09-15
- Last modified
- 2026-09-15
Affected products
- go-vikunja vikunja
- go-vikunja vikunja
Weakness type
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