Auth bypass in Step-security Harden-runner
CVE-2026-32947
Harden-Runner is a CI/CD security agent that works like an EDR for GitHub Actions runners. In versions 2.15.1 and below, a DNS over HTTPS (DoH) vulnerability allows attackers to bypass egress-policy: block network restrictions by tunneling…
EPSS: 0.003 (22.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Step-security Harden-runner — versions < 2.16
- Stepsecurity Harden-runner
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-32947?
- CVE-2026-32947 is a medium-severity vulnerability in Step-security Harden-runner, classified under Protection Mechanism Failure. CVSS score: 4.9/10. Published 2026-03-20.
- How severe is CVE-2026-32947?
- Medium severity. CVSS v3 base score is 4.9 out of 10.