CVE-2023-23939
This vulnerability only impacts versions before version 3.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Azure/setup-kubectl is a GitHub Action for installing Kubectl. This vulnerability only impacts versions before version 3. An insecure temporary creation of a file allows other actors on the Actions runner to replace the Kubectl binary created by this action because it is world writable. This Kubectl tool installer runs `fs.chmodSync(kubectlPath, 777)` to set permissions on the Kubectl binary, however, this allows any local user to replace the Kubectl binary. This allows privilege escalation to the user that can also run kubectl, most likely root. This attack is only possible if an attacker somehow breached the GitHub actions runner or if a user is utilizing an Action that maliciously executes this attack. This has been fixed and released in all versions `v3` and later. 775 permissions are used instead. Users are advised to upgrade. There are no known workarounds for this issue.
- CVSS 3.1
- 7.0 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.36% probability · 30th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-732
- Affected
- microsoft/azure setup kubectl
- Source
- security-advisories@github.com
References
- https://github.com/Azure/setup-kubectl/commit/d449d75495d2b9d1463555bb00ca3dca77a42ab6Patch
- https://github.com/Azure/setup-kubectl/security/advisories/GHSA-p756-rfxh-x63hVendor Advisory
- https://github.com/Azure/setup-kubectl/commit/d449d75495d2b9d1463555bb00ca3dca77a42ab6Patch
- https://github.com/Azure/setup-kubectl/security/advisories/GHSA-p756-rfxh-x63hVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.