CVE-2026-91985

Vikunja before 2.6.0 fails to properly restrict access to the link-share hash field in single-share read endpoints, allowing read-only members to obtain the share's secret credential. Attackers can exchange the disclosed hash for a link-share JWT at the share's permission level to escalate privileges and perform unauthorized writes or administrative actions.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-privilege-escalation-via-link-share-hash
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 17:17

NVD link : CVE-2026-91985

Mitre link : CVE-2026-91985

CVE.ORG link : CVE-2026-91985

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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