CVE-2021-29488 Creation of files outside the Download Folder through malicious PAR2 files
Attackers can write files outside the configured download directory using malicious PAR2 files, potentially overwriting system files.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-29488?
CVE-2021-29488 is a medium-severity path traversal vulnerability in sabnzbd, published on 7 May 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
SABnzbd is an open source binary newsreader. A vulnerability was discovered in SABnzbd that could trick the `filesystem.renamer()` function into writing downloaded files outside the configured Download Folder via malicious PAR2 files. A patch was released as part of SABnzbd 3.2.1RC1. As a workaround, limit downloads to NZBs without PAR2 files, deny write permissions to the SABnzbd process outside areas it must access to perform its job, or update to a fixed version.
Weakness: CWE-23
Which versions are affected by CVE-2021-29488?
It affects 1 product.
Products include Sabnzbd Sabnzbd.
How do I fix CVE-2021-29488?
Upgrade to a fixed version.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2021-29488 being exploited?
There is no known exploitation of CVE-2021-29488 in the wild and no public exploit code.
Other vulnerabilities in sabnzbd
Sources
Also known as DEBIAN-CVE-2021-29488, UBUNTU-CVE-2021-29488.