CVE-2026-91973 (GCVE-0-2026-91973)
Vulnerability from cvelistv5
Published
2026-09-15 15:18
Modified
2026-09-15 15:55
Severity ?
8.7 (High) - 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
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-307 - Improper Restriction of Excessive Authentication Attempts
Summary
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.
References
Impacted products
Vendor Product Version
go-vikunja vikunja Version: 0   ≤
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