CVE-2026-91971

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-4vh2-39rq-rq8j
https://www.vulncheck.com/advisories/vikunja-before-2.6.0-denial-of-service-via-avatar-upload

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 16:17

NVD link : CVE-2026-91971

Mitre link : CVE-2026-91971

CVE.ORG link : CVE-2026-91971

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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