Vulnerability · Published Sep 15, 2026 · Assigned by VulnCheck

CVE-2026-91968vikunja before 2.6.0 Denial of Service via unbounded filter recursion

Medium 6.5

In plain English

A medium-severity security flaw in vikunja from go-vikunja. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.4%top 62.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	code.vikunja.io/api	2.6.0	GHSA-xxc3-xpmc-vmvr
Go	code.vikunja.io/api	no fix listed	GO-2026-6759

Affected products (as reported)

Vendor	Product	Versions
go-vikunja	vikunja	2.5.0 – before 2.6.0

Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

GitHub Security Advisory (GHSA-xxc3-xpmc-vmvr) vendor-advisory
VulnCheck Advisory: vikunja before 2.6.0 Denial of Service via unbounded filter recursion third-party-advisory