Arbitrary environment-variable injection via unsanitized null bytes
Published Mar 2, 2023 · Updated Mar 5, 2025
Code injection in affected GitHub Enterprise Server releases allows remote authenticated users to set arbitrary environment variables. GitHub Actions on Windows runners improperly sanitizes null bytes in one environment-variable value, allowing that value to define additional variables. Exploitation requires existing permission to control environment-variable values used by an Actions workflow; published evidence establishes alteration of the runner process environment but not command execution.
Summary
What happened
Code injection in affected GitHub Enterprise Server releases allows remote authenticated users to set arbitrary environment variables. GitHub Actions on Windows runners improperly sanitizes null bytes in one environment-variable value, allowing that value to define additional variables. Exploitation requires existing permission to control environment-variable values used by an Actions workflow; published evidence establishes alteration of the runner process environment but not command execution.
The record
- CVE
- CVE-2023-22381
- Published
- Mar 2, 2023
- Updated
- Mar 5, 2025
- Vendor
- Product
- GitHub Enterprise Server
- Classifications
- CWE-94, CAPEC-77
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 2, 2023CVE publishedPublication date reported by the CVE source.
- Mar 5, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3.4.0 <=3.4.14 changes=[{"at":"3.4.15","status":"unaffected"}]
- Affected versionversion=3.5.0 <=3.5.11 changes=[{"at":"3.5.12","status":"unaffected"}]
- Affected versionversion=3.6.0 <=3.6.7 changes=[{"at":"3.6.8","status":"unaffected"}]
- Affected versionversion=3.7.0 <=3.7.4 changes=[{"at":"3.7.5","status":"unaffected"}]
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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