Server-Side Request Forgery (SSRF) Affecting actions-runner package, versions <2.337.0-r2


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.39% (31st percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-ACTIONSRUNNER-20337073
  • published30 Sept 2026
  • disclosed28 Sept 2026

Introduced: 28 Sep 2026

NewCVE-2026-101910  (opens in a new tab)
CWE-918  (opens in a new tab)

How to fix?

Upgrade Chainguard actions-runner to version 2.337.0-r2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream actions-runner package and not the actions-runner package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

ip-address is a library for parsing and manipulating IPv4 and IPv6 addresses in JavaScript. From 10.2.0 until 10.5.1, the Address6 isPrivate classifier in src/ipv6.ts does not recognize the NAT64 local-use range 64:ff9b:1::/48. Applications that combine isPrivate, isLoopback, and isLinkLocal for a trust-boundary decision can treat an internal IPv4 destination encoded through that range as external. Exploitation depends on a server network using an operator-selected NAT64 prefix within the local-use range. A successful bypass can cross the intended network trust boundary. This issue is fixed in version 10.5.1.

CVSS Base Scores

version 3.1