Hydra
CVE-2025-54864
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A07:2025 - Authentication Failures
ASVS 5.0
V6 - Authentication Authentication required for critical functions
MITRE ATT&CK
1 technique across 1 tactic: Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.9 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 0.10%. |
| Exploit ScenarioDerived | A remote attacker could access critical functionality without authentication by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAIv1 – Mar 28, 2026
Hydra is a continuous integration service for Nix based projects. Rated medium severity (CVSS 6.9), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Missing Authentication for Critical Function vulnerability could allow attackers to access critical functionality without authentication.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Require authentication for all sensitive operations, implement defense in depth.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Missing Authentication for Critical Function (CWE-306), which allows attackers to access critical functionality without authentication. Hydra is a continuous integration service for Nix based projects. Prior to commit f7bda02, /api/push-github and /api/push-gitea are called by the corresponding forge without HTTP Basic authentication. Both forges do however feature HMAC signing with a secret key. Triggering an evaluation can be very taxing on the infrastructure when large evaluations are done, introducing potential denial of service attacks on the host running the evaluator. This issue has been patched by commit f7bda02. A workaround involves blocking /api/push-github and /api/push-gitea via a reverse proxy. Affected products include: Nixos Hydra.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
2DescriptionGitHub Advisory
Hydra is a continuous integration service for Nix based projects. Prior to commit f7bda02, /api/push-github and /api/push-gitea are called by the corresponding forge without HTTP Basic authentication. Both forges do however feature HMAC signing with a secret key. Triggering an evaluation can be very taxing on the infrastructure when large evaluations are done, introducing potential denial of service attacks on the host running the evaluator. This issue has been patched by commit f7bda02. A workaround involves blocking /api/push-github and /api/push-gitea via a reverse proxy.
Executive ViewAI
Organizations using Hydra should be aware of notable risk from CVE-2025-54864, a missing authentication vulnerability rated CVSS 6.9. This could allow unauthorized access to protected resources. A patch is available and should be applied during regular vulnerability management.
Apply vendor patch. If patching is delayed: restrict network access, enable MFA, monitor auth logs.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)GitHub Advisory
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GitHub PoC
Exploit-DB