Vikunja Affected by DoS via Image Preview Generation

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-33474: 0.32% estimated exploitation activity in the next 30 days; percentile 25.47 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary - Vulnerability: Unbounded image decoding and resizing during preview generation lets an attacker exhaust CPU and memory with highly compressed but extremely large-dimension images. - Affected code: - Decoding without bounds: taskattachment.go:GetPreview - Resizing path: resizeImage - Endpoint invoking preview: GetTaskAttachment - Impact: First preview generation per attachment can allocate large memory and spend significant CPU; multiple attachments or concurrent requests can degrade or crash the service. - CVSS v3.1: 7.5 (AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) Preconditions - API running locally (http://localhost:8080). - Task attachments enabled: taskattachmentsenabled=true in Info. - Any authenticated user with write access to a task. How It Works - Preview generation decodes the full image via image.Decode and resizes to a target width. There are no guards on width/height or total pixels. A 10,000×10,000 PNG (~284 KB on disk) expands to ~100M pixels in memory during decode…

Published by the source

20 Mar 2026, 20:43 UTC

Last modified by the source

25 Mar 2026, 20:59 UTC

Source last checked

26 Oct 2026, 15:18 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-wc83-79hj-hpmq

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# Patch Next advisory brief: CVE-2026-33474

Advisory: Vikunja Affected by DoS via Image Preview Generation
IDs: CVE-2026-33474, GHSA-wc83-79hj-hpmq
Record: https://patchnext.com/advisories/cve-2026-33474 (revision 1, source checked 26 Oct 2026, 15:18 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code.vikunja.io/api 2.2.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.vikunja.io/api: affected >= 1.0.0-rc0, < 2.2.0; fixed in 2.2.0

## Suggested inspection (read-only)
- Go code.vikunja.io/api: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on code.vikunja.io/api.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-wc83-79hj-hpmq (GitHub-reviewed advisory GHSA-wc83-79hj-hpmq lists affected ranges: Go code.vikunja.io/api >=1.0.0-rc0 <2.2.0)

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