CVE-2026-91983

Vikunja before 2.6.0 contains an API token scope bypass vulnerability in task read endpoints where authorization fails to inspect query string parameters. Attackers with limited token scopes can use the expand parameter to access restricted data like comments, reactions, and time entries without proper permission verification.

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-9rg3-v78m-26q8
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-api-token-scope-bypass-via-expand-parameter
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-9rg3-v78m-26q8

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 16:17

NVD link : CVE-2026-91983

Mitre link : CVE-2026-91983

CVE.ORG link : CVE-2026-91983

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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