Privilege escalation in Gitea Act Runner
CVE-2026-58053
Gitea act_runner with the Docker backend (through act 0.262.0) passes a workflow's container.options string to the Docker job container's HostConfig and, when configured with privileged: false, forces only the Privileged flag off while merging options such as --pid=host, --cap-add, and --security-opt unchanged. A user who can run a workflow on a Docker-backed runner can create a job container with host namespaces and broad capabilities and escape to the host as root despite privileged mode being disabled.
Vulnerability class: Privilege Escalation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (36.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Gitea Act Runner — versions 0
Weakness classification (CWE)
References
- github.com/bikini/exploitarium/tree/main/gitea-act-runner-container-options-poc (exploit, third-party-advisory)
- www.vulncheck.com/advisories/gitea-act-runner-container-hardening-bypass-via-wo… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-58053?
- CVE-2026-58053 is a critical-severity vulnerability in Gitea Act Runner, classified under Improper Privilege Management. CVSS score: 9.9/10. Published 2026-06-28.
- How severe is CVE-2026-58053?
- Critical severity. CVSS v3 base score is 9.9 out of 10.