Symlink following allows leaking out-of-bound manifests and JSON files from Argo CD repo-server

Vulnerability Description

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Argo CD starting with version 0.7.0 and prior to versions 2.1.15m 2.2.9, and 2.3.4 is vulnerable to a symlink following bug allowing a malicious user with repository write access to leak sensitive files from Argo CD's repo-server. A malicious Argo CD user with write access for a repository which is (or may be) used in a directory-type Application may commit a symlink which points to an out-of-bounds file. Sensitive files which could be leaked include manifest files from other Applications' source repositories (potentially decrypted files, if you are using a decryption plugin) or any JSON-formatted secrets which have been mounted as files on the repo-server. A patch for this vulnerability has been released in Argo CD versions 2.3.4, 2.2.9, and 2.1.15. Users of versions 2.3.0 or above who do not have any Jsonnet/directory-type Applications may disable the Jsonnet/directory config management tool as a workaround.

References

• https://github.com/argoproj/argo-cd/security/advisories/GHSA-6gcg-hp2x-q54h
• https://github.com/argoproj/argo-cd/releases/tag/v2.1.15
• https://github.com/argoproj/argo-cd/releases/tag/v2.2.9
• https://github.com/argoproj/argo-cd/releases/tag/v2.3.4