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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vfxw-3x8p-2vjr
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-user-enumeration-via-v2-api
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vfxw-3x8p-2vjr

Configurations

No configuration.

History

21 Sep 2026, 19:17

Type	Values Removed	Values Added
References	~~() https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vfxw-3x8p-2vjr -~~	() https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vfxw-3x8p-2vjr -

Information

Published : 2026-09-15 16:17

Updated : 2026-09-21 19:17

NVD link : CVE-2026-91981

Mitre link : CVE-2026-91981

CVE.ORG link : CVE-2026-91981

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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