High severity7.5NVD Advisory· Published Sep 15, 2026· Updated Sep 16, 2026
CVE-2026-91973
CVE-2026-91973
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
code.vikunja.io/apiGo | < 2.6.0 | 2.6.0 |
Affected products
2- Range: <2.6.0
Patches
Vulnerability mechanics
References
6- github.com/advisories/GHSA-m469-88xx-8rx2ghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-91973ghsaADVISORY
- github.com/go-vikunja/vikunja/pull/3688ghsaWEB
- github.com/go-vikunja/vikunja/releases/tag/v2.6.0ghsaWEB
- github.com/go-vikunja/vikunja/security/advisories/GHSA-m469-88xx-8rx2nvdWEB
- www.vulncheck.com/advisories/vikunja-before-2.6.0-authentication-bypass-via-caldav-basicauthnvdWEB
News mentions
1- Go Vikunja: Twelve Vulnerabilities Including Privilege Escalation and Auth Bypass Disclosed TogetherVypr Intelligence · Sep 15, 2026