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TI-2026-40047 Aliases CVE-2026-55494

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

Priority HIGH 82CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-284.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0064 50th percentileScored 2026-11-07
Fix Fixed tugtainer (Quenary): 1.30.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Quenarytugtainerbefore 1.30.41.30.4Patch availableCNA
  • tugtainer VendorQuenary Affected before 1.30.4 Fixed in 1.30.4 Patch available CNA

Remediation

  • Fix · CNA tugtainer (Quenary) Fixed in 1.30.4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-55494
  2. 2026-10-23 EPSS moved to the 50th–90th percentile

References

Other 3

  • TI-2026-39865 Tugtainer: OIDC login remains accessible when OIDC_ENABLED is false CVSS 3.1CRITICAL 9.4
  • TI-2026-35252 Tugtainer has Server-Side Template Injection in notification templates that leads to Remote Code Execution CVSS 3.1CRITICAL 9.9
  • TI-2026-44487 Tugtainer: Authenticated SSRF via arbitrary notification URLs in test_notification endpoint CVSS 3.1CRITICAL 9.1
  • TI-2026-19209 Tugtainer vulnerable to Password Exposure via URL Query Parameter CVSS 3.1CRITICAL 9.1
  • TI-2026-59429 Tugtainer: OIDC id_token claims accepted without signature/audience/expiry verification CVSS 3.1HIGH 8.1
  • TI-2025-42655 Tugtainer has RCE in Agent Command Execution Api CVSS 4.0HIGH 8.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences