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vulnerability

Ubuntu: USN-7603-1 (CVE-2023-43655): Composer vulnerabilities

Severity
7
CVSS
(AV:N/AC:H/Au:M/C:C/I:C/A:C)
Published
Sep 29, 2023
Added
Jun 26, 2025
Modified
Mar 27, 2026

Description

Composer is a dependency manager for PHP. Users publishing a composer.phar to a public web-accessible server where the composer.phar can be executed as a php file may be subject to a remote code execution vulnerability if PHP also has `register_argc_argv` enabled in php.ini. Versions 2.6.4, 2.2.22 and 1.10.27 patch this vulnerability. Users are advised to upgrade. Users unable to upgrade should make sure `register_argc_argv` is disabled in php.ini, and avoid publishing composer.phar to the web as this is not best practice.

Solution

ubuntu-pro-upgrade-composer
Title
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