Vulnerability in Step-Security Harden-Runner
CVE-2026-25598
Harden-Runner is a CI/CD security agent that works like an EDR for GitHub Actions runners. Prior to 2.14.2, a security vulnerability has been identified in the Harden-Runner GitHub Action (Community Tier) that allows outbound network connections to evade audit logging. Specifically, outbound traffic using the sendto, sendmsg, and sendmmsg socket system calls can bypass detection and logging when using egress-policy: audit. This vulnerability is fixed in 2.14.2.
EPSS: 0.003 (23.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
Affected products
- Step-security Harden-runner — versions < 2.14.2
- Stepsecurity Harden-runner
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-25598?
- CVE-2026-25598 is a medium-severity vulnerability in Step-Security Harden-Runner, classified under CWE-778. CVSS score: 5.3/10. Published 2026-02-09.
- How severe is CVE-2026-25598?
- Medium severity. CVSS v3 base score is 5.3 out of 10.