CVE-2026-91985 Details
Description
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.
A vulnerability in Vikunja versions prior to 2.6.0 allows read-only members to access the link-share hash field through single-share read endpoints. This exposure enables them to obtain a share's secret credential, which can be exchanged for a link-share JWT at the corresponding permission level. As a result, unauthorized writes or administrative actions can be performed. The issue arises from improper access restrictions, leaving a gap that read-only members can exploit to escalate privileges within shared projects.
Users are advised to update to Vikunja version 2.6.0 or later, where this vulnerability has been patched.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Sep 15, 2026CISA-ADP
Assessed Sep 15, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g | [email protected] | AdvisoryExploitRemedyVendor |
| https://www.vulncheck.com/advisories/vikunja-before-2.6.0-privilege-escalation-via-link-share-hash | [email protected] | Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-200 | Exposure of Sensitive Information to an Unauthorized Actor | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Vikunja | <= 2.5.0 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 15, 2026 | CVE Modified | CISA-ADP |
| Sep 15, 2026 | New CVE Received | [email protected] |
Volerion