Vulnerability in Azure Setup-Kubectl
CVE-2023-23939
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.9 (Low). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (27.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Azure Setup-Kubectl — versions < 3
- Microsoft Azure Setup Kubectl
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2023-23939?
- CVE-2023-23939 is a low-severity vulnerability in Azure Setup-Kubectl, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 3.9/10. Published 2023-03-06.
- How severe is CVE-2023-23939?
- Low severity. CVSS v3 base score is 3.9 out of 10.