Harden-Runner is a CI/CD security agent that works like an EDR for GitHub Actions runners. In versions 2.15.1 and below, the Harden-Runner that allows bypass of the egress-policy: block network restriction using DNS queries over TCP. Egress policies are enforced on GitHub runners by filtering outbound connections at the network layer. When egress-policy: block is enabled with a restrictive allowed-endpoints list (e.g., only github.com:443), all non-compliant traffic should be denied. However, DNS queries over TCP, commonly used for large responses or fallback from UDP, are not adequately restricted. Tools like dig can explicitly initiate TCP-based DNS queries (+tcp flag) without being blocked. This vulnerability requires the attacker to already have code execution capabilities within the GitHub Actions workflow. The issue has been fixed in version 2.16.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-693",
"CWE-863"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/32xxx/CVE-2026-32946.json"
}{
"source": [
"AFFECTED_FIELD",
"CPE_RANGE",
"REFERENCES"
],
"cpe": "cpe:2.3:a:stepsecurity:harden-runner:*:*:*:*:community:*:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "2.16.0"
}
]
}