Skip to content
Fencer Intel
critical 9.8

CVE-2026-55494 json

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

published 4mo ago modified last mo. also EUVD-2026-90193 , GHSA-wgw2-c96g-p7h7

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository Quenary/tugtainer. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 51%
public exploits
0
none known

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.

Patch / fix

  • quenary tugtainer 1.30.4

Is CVE-2026-55494 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
total
Assessed
last mo.

Exploit prediction

0.64% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/Quenary/tugtainer/security/advisories/GHSA-wgw2-c96g-p7h7 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Quenary tugtainer

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of Quenary/tugtainer published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.