USN-7616-1: logback vulnerabilities

Publication date

2 July 2025

Overview

Several security issues were fixed in logback.


Packages

  • logback - A reliable, generic, fast and flexible logging library for Java

Details

It was discovered that logback could read malicious configuration files
from LDAP servers. An attacker with the required permissions could possibly
use this issue to execute arbitrary code. This issue only affected Ubuntu
16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-42550) It was
discovered that logback contained a serialization vulnerability. An
attacker could possibly use this issue to cause a denial of service.
(CVE-2023-6378)

It was discovered that logback could read malicious configuration files
from LDAP servers. An attacker with the required permissions could possibly
use this issue to execute arbitrary code. This issue only affected Ubuntu
16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-42550) It was
discovered that logback contained a serialization vulnerability. An
attacker could possibly use this issue to cause a denial of service.
(CVE-2023-6378)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
22.04 jammy liblogback-java –  1:1.2.10-1ubuntu0.1~esm1  
20.04 focal liblogback-java –  1:1.2.3-5ubuntu0.1~esm1  
18.04 bionic liblogback-java –  1:1.2.3-2ubuntu1~18.04.1+esm1  
16.04 xenial liblogback-java –  1:1.1.3-2ubuntu0.1~esm1  

Reduce your security exposure

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