Vikunja before 2.6.0 Denial of Service via Avatar Upload (CVE-2026-91971) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-91971

Vikunja before 2.6.0 Denial of Service via Avatar Upload

Answer in brief

CVE-2026-91971 records a Unknown severity vulnerability in Vikunja before 2.6.0 Denial of Service via Avatar Upload. The current sources do not mark it as known exploited. The current feed maps go-vikunja/vikunja (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 15, 2026Updated Sep 15, 2026Source checked Sep 15, 2026First seen by HOL Sep 15, 2026Material review Sep 15, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps go-vikunja/vikunja (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
go-vikunja/vikunjageneric	>=0 <2.6.0	2.6.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for go-vikunja/vikunja.
Review the reported fix. Update go-vikunja/vikunja to 2.6.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 15, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.