Medium severity · published Sep 15, 2026
CVE-2026-91968
vikunja before 2.6.0 Denial of Service via unbounded filter recursion
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
vikunja versions before 2.6.0 contain a resource exhaustion vulnerability in the task-filter endpoint that accepts deeply nested filter expressions without recursion depth limits. Authenticated attackers can supply thousands of nested parentheses in the filter query parameter to exhaust memory and terminate the API process.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VI
vikunja · go-vikunja
2.5.0 before 2.6.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91968
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91968
github.com
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-xxc3-xpmc-vmvr
www.vulncheck.com
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-denial-of-service-via-unbounded-filter-recursion
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