CVE-2023-31128: nextcloud cookbook OS Command Injection

Vulnerability summary

CVE-2023-31128 is a high (CVSS 8.8) OS Command Injection vulnerability in nextcloud cookbook. EPSS estimates a 3.34% chance of exploitation in the next 30 days, higher than 88.5% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 26-05-2023
   PublishedVulnerability first disclosed.
2. 14-01-2025
   Last modifiedVulnerability information updated.

Description

NextCloud Cookbook is a recipe library app. Prior to commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch, the `pull-checks.yml` workflow is vulnerable to command injection attacks because of using an untrusted `github.head_ref` field. The `github.head_ref` value is an attacker-controlled value. Assigning the value to `zzz";echo${IFS}"hello";#` can lead to command injection. Since the permission is not restricted, the attacker has a write-access to the repository. This issue is fixed in commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch. There is no risk for the user of the app within the NextCloud server. This only affects the main repository and possible forks of it. Those who have forked the NextCloud Cookbook repository should make sure their forks are on the latest version to prevent code injection attacks and similar.

• CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.