title: Code injection in GitHub Enterprise Server leading to arbitrary environment variables in GitHub Actions
description: A code injection vulnerability was identified in GitHub Enterprise Server that allowed setting arbitrary environment variables from a single environment variable value in GitHub Actions when using a Windows based runner. To exploit this vulnerability, an attacker would need existing permission to control the value of environment variables for use with GitHub Actions. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.8.0 and was fixed in versions 3.4.15, 3.5.12, 3.6.8, 3.7.5. This vulnerability was reported via the GitHub Bug Bounty program.
problem types: CWE-94 Improper Control of Generation of Code ('Code Injection')
affected:
{
defaultStatus: affected
product: Enterprise Server
vendor: GitHub
versions:
changes: [at: 3.4.15, status: unaffected], lessThanOrEqual: 3.4.14, status: affected, version: 3.4.0, versionType: semver
changes: [at: 3.5.12, status: unaffected], lessThanOrEqual: 3.5.11, status: affected, version: 3.5.0, versionType: semver
changes: [at: 3.6.8, status: unaffected], lessThanOrEqual: 3.6.7, status: affected, version: 3.6.0, versionType: semver
changes: [at: 3.7.5, status: unaffected], lessThanOrEqual: 3.7.4, status: affected, version: 3.7.0, versionType: semver
status: unaffected, version: 3.8.0
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 4.1
baseSeverity: MEDIUM
confidentialityImpact: LOW
integrityImpact: LOW
privilegesRequired: HIGH
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L
version: 3.1
]
format: CVSS
scenarios: GENERAL