CVE-2026-76216

Vikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards. Attackers with a link-share JWT can remove victims from teams, enumerate and delete victim bot users, or read team rosters by exploiting id collisions in the autoincrement space.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-32r8-5843-4qw2
https://www.vulncheck.com/advisories/vikunja-through-principal-type-confusion-via-linksharing

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 14:17

Updated : 2026-09-16 20:18

NVD link : CVE-2026-76216

Mitre link : CVE-2026-76216

CVE.ORG link : CVE-2026-76216

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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