CVE-2026-91971

high

Description

Vikunja before 2.6.0 fails to apply pixel decode limits to avatar and project-background upload endpoints, allowing authenticated users to upload crafted images that decode to excessive pixel counts. Attackers can upload small images with extreme aspect ratios that consume significant CPU and memory during processing, causing denial of service through repeated or concurrent uploads.

References

https://www.vulncheck.com/advisories/vikunja-before-2.6.0-denial-of-service-via-avatar-upload

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-4vh2-39rq-rq8j

Details

Source: Mitre, NVD

Published: 2026-09-15

Updated: 2026-09-16

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

CVSS v4

Base Score: 7.1

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00338