CVE-2021-29157 Path traversal in n/a

High 7.5 Published 28 Jun 2021 Updated 3 Aug 2024

An attacker with local filesystem access can exploit path traversal in Dovecot's OAuth2 JWT validation to bypass authentication using a controlled key.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2021-29157?

CVE-2021-29157 is a high-severity path traversal vulnerability in Dovecot Dovecot, published on 28 Jun 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Dovecot before 2.3.15 allows ../ Path Traversal. An attacker with access to the local filesystem can trick OAuth2 authentication into using an HS256 validation key from an attacker-controlled location. This occurs during use of local JWT validation with the posix fs driver.

Weakness: CWE-22

Which versions are affected by CVE-2021-29157?

It affects 2 products.

Products include Dovecot Dovecot, Fedoraproject Fedora.

How do I fix CVE-2021-29157?

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-2021-29157 being exploited?

There is no known exploitation of CVE-2021-29157 in the wild and no public exploit code.

All Dovecot Dovecot vulnerabilities

Sources

Also known as ALPINE-CVE-2021-29157, AZL-7195, DEBIAN-CVE-2021-29157, GHSA-89g9-v7q6-px25.