CVE-2021-4287 ReFirm Labs binwalk Archive Extraction extractor.py symlink
Attackers can exploit symlink following in binwalk's archive extraction to read or modify arbitrary files on the system.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-4287?
CVE-2021-4287 is a medium-severity path traversal vulnerability in ReFirm Labs binwalk, published on 27 Dec 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A vulnerability, which was classified as problematic, was found in ReFirm Labs binwalk up to 2.3.2. Affected is an unknown function of the file src/binwalk/modules/extractor.py of the component Archive Extraction Handler. The manipulation leads to symlink following. It is possible to launch the attack remotely. Upgrading to version 2.3.3 is able to address this issue. The name of the patch is fa0c0bd59b8588814756942fe4cb5452e76c1dcd. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-216876.
Which versions are affected by CVE-2021-4287?
3 open source packages ship an affected version, including binwalk. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
binwalk PyPI | All versions | 2.3.3 |
binwalk PyPI | All versions | 2.3.3 |
binwalk PyPI | All versions | 2.3.3 |
Products include Microsoft Binwalk.
How do I fix CVE-2021-4287?
Upgrade binwalk to 2.3.3 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2021-4287 being exploited?
There is no known exploitation of CVE-2021-4287 in the wild and no public exploit code.
Other vulnerabilities in ReFirm Labs binwalk
Sources
Also known as DEBIAN-CVE-2021-4287, GHSA-8m3f-g62j-3vx8, PYSEC-2026-788, UBUNTU-CVE-2021-4287.