What is CVE-2026-91981?

CVE-2026-91981 is a medium-severity vulnerability in Go-Vikunja Vikunja, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-09-15.

How severe is CVE-2026-91981?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Information disclosure in Go-Vikunja Vikunja

CVE-2026-91981

Vikunja versions before 2.6.0 fail to properly validate link-share tokens in the v2 API user search endpoints. Attackers with a read-only share link can enumerate project users via the projects endpoint and confirm arbitrary usernames exist via the global search endpoint.

Vulnerability class: Information Disclosure

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

Affected products

Go-vikunja Vikunja

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

disclosure@vulncheck.com (vendor-advisory)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-91981?: CVE-2026-91981 is a medium-severity vulnerability in Go-Vikunja Vikunja, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-09-15.
How severe is CVE-2026-91981?: Medium severity. CVSS v3 base score is 4.3 out of 10.