Vikunja: WebSocket authentication ignores server-side session state, so revoked sessions keep receiving live pushes

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:H/I:N/A:N

EPSS

• CVE-2026-111917: 0.36% estimated exploitation activity in the next 30 days; percentile 29.30 (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 Vikunja v2.6.0 introduced server-side sessions with revocation semantics: `DELETE /api/v2/user/sessions/{id}` documents "Revokes a specific session by its UUID", and enabling TOTP calls `DeleteAllUserSessions` to invalidate all sessions. The WebSocket endpoint accepts any cryptographically valid user JWT without ever resolving its `sid` (session id) claim against the sessions table. A connection authenticated before revocation stays authenticated and continues to receive live pushes indefinitely, and even brand-new WebSocket connections are accepted with a token whose session was deleted. The revocation feature therefore does not cover the WebSocket boundary at all.

Details User access JWTs carry a session reference: `NewUserJWTAuthtoken` (`pkg/modules/auth/auth.go:188`) sets `claims["sid"] = sessionID`, and the API login-session documentation describes the claim as tying the JWT to a server-side session. On the HTTP side nothing consumes the claim per request either…

Published by the source

9 Oct 2026, 20:57 UTC

Last modified by the source

27 Oct 2026, 15:30 UTC

Source last checked

28 Oct 2026, 06:30 UTC

1. Revision 5 · amended · 28 Oct 2026

   Amended from osv record GHSA-4hv6-xc92-j86g

2. Revision 4 · amended · 27 Oct 2026

   Amended from ghsa record GHSA-4hv6-xc92-j86g

3. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-4hv6-xc92-j86g

4. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6715

5. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-4hv6-xc92-j86g

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# Patch Next advisory brief: CVE-2026-111917

Advisory: Vikunja: WebSocket authentication ignores server-side session state, so revoked sessions keep receiving live pushes
IDs: CVE-2026-111917, GHSA-4hv6-xc92-j86g
Record: https://patchnext.com/advisories/cve-2026-111917 (revision 5, source checked 28 Oct 2026, 06:30 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 2.7.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.vikunja.io/api: affected >= 2.3.0, < 2.7.0; fixed in 2.7.0

## 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://osv.dev/vulnerability/GO-2026-6715 (OSV record GO-2026-6715 lists affected ranges: Go code.vikunja.io/api >=0)
- Verified: https://osv.dev/vulnerability/GHSA-4hv6-xc92-j86g (OSV record GHSA-4hv6-xc92-j86g lists affected ranges: Go code.vikunja.io/api >=2.3.0 <=2.6.0)
- Verified: https://github.com/advisories/GHSA-4hv6-xc92-j86g (GitHub-reviewed advisory GHSA-4hv6-xc92-j86g lists affected ranges: Go code.vikunja.io/api >=2.3.0 <=2.6.0)
- Verified: https://osv.dev/vulnerability/GHSA-4hv6-xc92-j86g (OSV record GHSA-4hv6-xc92-j86g lists affected ranges: Go code.vikunja.io/api >=2.3.0 <2.7.0 (fixed))

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