High 7.5Published Sep 15, 2026

CVE-2026-91973Vikunja before 2.6.0 Authentication Bypass via CalDAV BasicAuth

Updated under an hour ago (2026-10-19 06:50 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for go-vikunja vikunja

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-307
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Sep 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

go-vikunja vikunja go_vikunja:vikunja (from the name)	before 2.6.0; 2.6.0 not affected	CNA record

References

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-m469-88xx-8rx2vendor-advisory
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-authentication-bypass-via-caldav-basicauththird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.