CVE-2023-23939 Azure/setup-kubectl: Escalation of privilege vulnerability for v3 and lower
Insecure file permissions in Azure setup-kubectl allow local attackers to replace the binary, leading to privilege escalation on the runner.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-23939?
CVE-2023-23939 is a low-severity vulnerability in Azure setup-kubectl, published on 6 Mar 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-732
Which versions are affected by CVE-2023-23939?
1 open source package ship an affected version, including Azure/setup-kubectl. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
Azure/setup-kubectl GitHub Actions | All versions | 3 |
Products include Microsoft Azure Setup Kubectl.
How do I fix CVE-2023-23939?
Upgrade Azure/setup-kubectl to 3 or later.
Is CVE-2023-23939 being exploited?
There is no known exploitation of CVE-2023-23939 in the wild and no public exploit code.
Sources
Also known as GHSA-p756-rfxh-x63h.