CVE-2020-10518 Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server

High 8.8 Published 27 Aug 2020 Updated 4 Aug 2024

Attackers with site creation permissions can execute arbitrary commands on GitHub Enterprise Server via unsafe GitHub Pages parser configurations.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2020-10518?

CVE-2020-10518 is a high-severity command injection vulnerability in GitHub Enterprise Server, published on 27 Aug 2020. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

A remote code execution vulnerability was identified in GitHub Enterprise Server that could be exploited when building a GitHub Pages site. User-controlled configuration of the underlying parsers used by GitHub Pages were not sufficiently restricted and made it possible to execute commands on the GitHub Enterprise Server instance. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 2.22 and was fixed in 2.21.6, 2.20.15, and 2.19.21. The underlying issues contributing to this vulnerability were identified both internally and through the GitHub Security Bug Bounty program.

Weakness: CWE-77

Which versions are affected by CVE-2020-10518?

It affects 1 product.

Products include Github Github.

How do I fix CVE-2020-10518?

No fix has been published for CVE-2020-10518 yet. Limit exposure of the affected software until one is available.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2020-10518 being exploited?

There is no known exploitation of CVE-2020-10518 in the wild and no public exploit code.

Sources

Also known as GHSA-m5vm-44r4-56mf.