CVE-2021-31566 Path traversal in libarchive
A local attacker can exploit improper link resolution in libarchive to modify file permissions and gain privileges by tricking a user into extracting a malicious archive.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-31566?
CVE-2021-31566 is a high-severity path traversal vulnerability in Debian Debian Linux, published on 23 Aug 2022. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
An improper link resolution flaw can occur while extracting an archive leading to changing modes, times, access control lists, and flags of a file outside of the archive. An attacker may provide a malicious archive to a victim user, who would trigger this flaw when trying to extract the archive. A local attacker may use this flaw to gain more privileges in a system.
Weakness: CWE-59
Which versions are affected by CVE-2021-31566?
It affects 14 products.
Linux distribution packages (7)
libarchive SUSE:Linux Enterprise Micro 5.3 | All versions | 3.5.1-150400.3.9.1 |
libarchive SUSE:Linux Enterprise Module for Basesystem 15 SP3 | All versions | 3.4.2-150200.4.12.1 |
libarchive SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 3.5.1-150400.3.9.1 |
libarchive SUSE:Linux Enterprise Module for Development Tools 15 SP3 | All versions | 3.4.2-150200.4.12.1 |
libarchive SUSE:Linux Enterprise Module for Development Tools 15 SP4 | All versions | 3.5.1-150400.3.9.1 |
libarchive openSUSE:Leap 15.3 | All versions | 3.4.2-150200.4.12.1 |
libarchive openSUSE:Leap 15.4 | All versions | 3.5.1-150400.3.9.1 |
Products include Debian Debian Linux, Fedoraproject Fedora, Libarchive Libarchive, Redhat Codeready Linux Builder, Redhat Enterprise Linux, Redhat Enterprise Linux Eus and 8 more.
How do I fix CVE-2021-31566?
Apply the vendor's patch.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2021-31566 being exploited?
There is no known exploitation of CVE-2021-31566 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2021-31566, CLSA-2026-1777307149, CLSA-2026-1777544831, DEBIAN-CVE-2021-31566, GHSA-mg62-fpgc-6hjj, JLSEC-2025-236 and 3 more.