---
id: CVE-2026-91985
title: >-
  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
summary: >-
  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-…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-200
vendor: go-vikunja
product: vikunja
affected:
  - vikunja < 2.6.0
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:49:18.987'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91985'
references:
  - url: >-
      https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/vikunja-before-2.6.0-privilege-escalation-via-link-share-hash
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qfwc-vx6f-3g6g
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-15T16:03:46.456174Z'
ingestedAt: '2026-09-15T15:39:12.910Z'
epss: 0.00381
epssPercentile: 0.31963
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.