Medium severity · published Sep 15, 2026
CVE-2026-91984
Vikunja before 2.6.0 Broken Object-Level Authorization via task-position
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Vikunja before 2.6.0 fails to validate that user-supplied project_view_id in task-position requests belongs to the task's project. Authenticated attackers can insert task position rows into arbitrary other tenant project views via POST or PUT task-position endpoints.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VI
vikunja · go-vikunja
before 2.6.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91984
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91984
github.com
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-w39f-h553-h2mx
www.vulncheck.com
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-broken-object-level-authorization-via-task-position
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