--- title: "CVE-2023-43655\n | Ubuntu" description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/CVE-2023-43655?format=md keywords: index, follow --- # CVE-2023-43655 Publication date 29 September 2023 Last updated 2 July 2025 --- Ubuntu priority **Medium** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **6.4 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2023-43655?format=md#impact-score) Toggle side navigation ## 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. ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | composer | 26.04 LTS resolute | Not affected | | 25.10 questing | Not affected | | 25.04 plucky | Not affected | | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 23.10 mantic | Ignored end of life, was needs-triage | | 23.04 lunar | Ignored end of life, was needs-triage | | 22.04 LTS jammy | Fixed 2.2.6-2ubuntu4+esm1 Ubuntu Pro | | 20.04 LTS focal | Fixed 1.10.1-1ubuntu0.1~esm2 Ubuntu Pro | | 18.04 LTS bionic | Fixed 1.6.3-1ubuntu0.1~esm2 Ubuntu Pro | | 16.04 LTS xenial | Fixed 1.0.0~beta2-1ubuntu0.1~esm2 Ubuntu Pro | | 14.04 LTS trusty | Not in release | --- * [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) * [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses) ### Get expanded security coverage with Ubuntu Pro Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use. [Get Ubuntu Pro](https://ubuntu.com/pro) [30-day free trial](https://ubuntu.com/pro/free-trial) ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 6.4 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | High | | Privileges required | High | | User interaction | Required | | Scope | Unchanged | | Confidentiality impact | High | | Integrity impact | High | | Availability impact | High | * Scores | Parameter | Value | | --- | --- | | Base score | 6.4 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-43655) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-43655) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2023-43655) * [Debian](https://security-tracker.debian.org/tracker/CVE-2023-43655) ### Related Ubuntu Security Notices (USN) + [USN-7603-1](https://usn.ubuntu.com/USN-7603-1) + Composer vulnerabilities + 30 June 2025 ### Other references * * * * * * * *