Api: Duplicate Advisory: Vikunja: Unbounded image decode on avatar and project-background uploads enables decode/resize amplification
Description
Vikunja versions up to 2.5.0 have a vulnerability in the avatar and project-background upload endpoints where pixel decode limits are not enforced. This allows authenticated users to upload crafted images that decode to very large pixel counts, consuming excessive CPU and memory resources. The flaw can lead to denial of service through resource exhaustion caused by repeated or concurrent uploads. This vulnerability has a CVSS score of 6.5, indicating a high severity impact on availability.
CVSS v3.1
Score 6.5medium
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Vikunja before version 2.6.0 does not enforce limits on pixel decoding for images uploaded as avatars or project backgrounds. Authenticated users can exploit this by uploading small images with extreme aspect ratios that expand to large pixel counts when decoded. This results in high CPU and memory usage during image processing, enabling denial of service conditions through resource exhaustion. The vulnerability is tracked as CWE-400 (Uncontrolled Resource Consumption).
Potential Impact
The vulnerability impacts availability by enabling denial of service through excessive CPU and memory consumption during image decoding and resizing. There is no impact on confidentiality or integrity. Exploitation requires authenticated access. No known exploits in the wild have been reported.
Mitigation Recommendations
A fix is available in Vikunja version 2.6.0 and later, which applies pixel decode limits to the affected upload endpoints. Users should upgrade to version 2.6.0 or later to remediate this issue. Since this is not a cloud service, remediation depends on applying the official patch. Patch status is confirmed by the version information provided.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-69rj-q3v9-vffp
- Osv Schema Version
- 1.4.0
- Ecosystems
- ["Go"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6ac96e4c2cdf04f65689a6bc
Added to database: 10/09/2026, 22:44:28 UTC
Last enriched: 10/09/2026, 22:48:10 UTC
Last updated: 10/09/2026, 22:48:10 UTC
Views: 2
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.