CVE-2021-41131 Explained : Impact and Mitigation
Learn about CVE-2021-41131, a high-severity path traversal vulnerability in python-tuf that allows arbitrary file overwrites. Find out how to mitigate and prevent this security issue.
python-tuf is a Python reference implementation of The Update Framework with a path traversal vulnerability that can lead to arbitrary file overwrites.
Understanding CVE-2021-41131
What is CVE-2021-41131?
CVE-2021-41131 is a high-severity path traversal vulnerability in python-tuf, allowing an attacker to overwrite files ending in '.json' on the client system.
The Impact of CVE-2021-41131
The vulnerability can lead to file overwrites anywhere on the client system, posing a risk to integrity. However, certain mitigating factors limit its overall impact.
Technical Details of CVE-2021-41131
Vulnerability Description
The issue stems from a path traversal vulnerability in python-tuf's rolename handling, enabling malicious actors to tamper with files.
Affected Systems and Versions
- Product: python-tuf
- Vendor: theupdateframework
- Versions Affected: < 0.19
Exploitation Mechanism
- Requires arbitrary rolename selection for delegated targets metadata
- Involves inserting new metadata for the path-traversing role
- Relies on getting the role delegated by existing targets metadata
Mitigation and Prevention
Immediate Steps to Take
- Upgrade to version 0.19 or newer
- Code changes are necessary; no workarounds are available
Long-Term Security Practices
- Restrict the character set for rolenames
- Store metadata in non-vulnerable file names
Patching and Updates
Install the fix available in python-tuf version 0.19 or above.