CVE-2025-32955 Harden-Runner Evasion of 'disable-sudo' policy
Attackers can bypass sudo restrictions in Harden-Runner by leveraging Docker group membership to gain root access on CI/CD runners.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-32955?
CVE-2025-32955 is a medium-severity vulnerability in step-security harden-runner, published on 21 Apr 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Harden-Runner is a CI/CD security agent that works like an EDR for GitHub Actions runners. Versions from 0.12.0 to before 2.12.0 are vulnerable to `disable-sudo` bypass. Harden-Runner includes a policy option `disable-sudo` to prevent the GitHub Actions runner user from using sudo. This is implemented by removing the runner user from the sudoers file. However, this control can be bypassed as the runner user, being part of the docker group, can interact with the Docker daemon to launch privileged containers or access the host filesystem. This allows the attacker to regain root access or restore the sudoers file, effectively bypassing the restriction. This issue has been patched in version 2.12.0.
Which versions are affected by CVE-2025-32955?
1 open source package ship an affected version, including step-security/harden-runner.
| Package | Affected | Fixed in |
|---|---|---|
step-security/harden-runner GitHub Actions | From 0.12.0 | 2.12.0 |
How do I fix CVE-2025-32955?
Upgrade step-security/harden-runner to 2.12.0 or later.
Is CVE-2025-32955 being exploited?
There is no known exploitation of CVE-2025-32955 in the wild and no public exploit code.
Sources
Also known as GHSA-mxr3-8whj-j74r.