Tugtainer: OIDC login reachable while OIDC is disabled
Summary
Tugtainer, a self-hosted tool for automating Docker container updates, still starts the OIDC login flow when OIDC_ENABLED is set to false. A direct request to /auth/oidc/login returns a redirect to the configured OIDC authorization endpoint, which bypasses the intended disable switch. The flaw requires no credentials, only network access to the web UI; whether a login can complete depends on the OIDC setup, and a related OIDC callback issue (GHSA-crjc-6vc7-xrfh) should be reviewed as well.
Affected
- Quenary Tugtainer versions before 1.30.3
Fixed in
- Fixed in Tugtainer 1.30.3 (fix commit 76371db). Upgrade to the latest release and check its changelog.
Workaround
- No vendor workaround known.
- Block GET requests to /auth/oidc/login at a WAF or reverse proxy on instances where OIDC is not used.
- Restrict outbound traffic from the Tugtainer host to approved OIDC providers.
Exploitation
- CISA SSVC: exploitation status PoC, automatable yes, technical impact total.
- No evidence of exploitation in the wild found.
- A public PoC exists for the related issue GHSA-crjc-6vc7-xrfh, not confirmed for this CVE.
Our recommendation
- Inventory all Tugtainer instances and their versions.
- Upgrade to version 1.30.3 or later.
- Do not expose the web UI directly to the internet; place it behind a VPN or an authenticating reverse proxy.
- Review logs for requests to /auth/oidc/login on instances where OIDC is not used.
- If OIDC is used, also address GHSA-crjc-6vc7-xrfh.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub Security Advisory GHSA-rg7c-vpfp-2w43 github.com
- Fix commit 76371db github.com
- Release v1.30.3 github.com
- OSV CVE-2026-55181 osv.dev
- TheHackerWire analysis www.thehackerwire.com
- Strix CVE page www.strix.ai
- GitHub Security Advisory GHSA-crjc-6vc7-xrfh github.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 00:21.
Original description (NVD)
Tugtainer is a self-hosted app for automating updates of Docker containers. Prior to version 1.30.3, Tugtainer's OIDC authentication can still be initiated even when OIDC_ENABLED=false. The /auth/oidc/enabled endpoint correctly reports that OIDC is disabled. However, a direct request to /auth/oidc/login still starts the OIDC login flow, returns HTTP 302, sets an oidc_state cookie, and redirects the user to the configured OIDC authorization endpoint. This bypasses the intended OIDC disable switch. This issue has been patched in version 1.30.3.
NVD references (4)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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