CVE-2026-91981

MediumCVSS 4.3/10Last modified Sep 21, 2026

Description

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.

Metrics

CVSS 3.1 4.3/10CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Sep 15, 2026
Last modified
Sep 21, 2026
NVD status
Deferred

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CVE-2026-91981: Medium severity, CVSS 4.3 | Vulnix