Tugtainer: Unauthenticated access to Tugtainer Agent Docker management APIs when AGENT_SECRET is unset (CVE-2026-55494) | HOL Guard CVE

Critical · CVSS 9.8CVE-2026-55494

Tugtainer: Unauthenticated access to Tugtainer Agent Docker management APIs when AGENT_SECRET is unset

Answer in brief

CVE-2026-55494 records a Critical severity (CVSS 9.8) vulnerability in Tugtainer: Unauthenticated access to Tugtainer Agent Docker management APIs when AGENT_SECRET is unset. The current sources do not mark it as known exploited. The current feed maps Quenary/tugtainer (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 30, 2026Updated Sep 30, 2026Source checked Sep 30, 2026First seen by HOL Sep 30, 2026Material review Sep 30, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.8
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 9.8. 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 Quenary/tugtainer (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Quenary/tugtainergeneric	<1.30.4	1.30.4

Recommended response

Check inventory. Check lockfiles and deployed manifests for Quenary/tugtainer.
Review the reported fix. Update Quenary/tugtainer to 1.30.4 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 30, 2026

Sources and claim methodology

Upstream source description

Tugtainer is a self-hosted app for automating updates of Docker containers. Prior to version 1.30.4, Tugtainer Agent allows unauthenticated access to Docker management APIs when AGENT_SECRET is not configured. The Agent uses request signatures to protect its API routes. However, in agent/auth.py, the signature verification function returns successfully if Config.AGENT_SECRET is empty. This causes protected Agent APIs to become accessible without authentication. This issue has been patched in version 1.30.4.

Quoted source text, attributed separately from HOL analysis.