Composer
CVE-2021-41116
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Command injection prevention
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could inject arbitrary commands into system command execution by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
Composer is an open source dependency manager for the PHP language. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Command Injection vulnerability could allow attackers to inject arbitrary commands into system command execution.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Use parameterized APIs, avoid shell execution, validate input with strict allowlists.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in composer
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Command Injection (CWE-77), which allows attackers to inject arbitrary commands into system command execution. Composer is an open source dependency manager for the PHP language. In affected versions windows users running Composer to install untrusted dependencies are subject to command injection and should upgrade their composer version. Other OSs and WSL are not affected. The issue has been resolved in composer versions 1.10.23 and 2.1.9. There are no workarounds for this issue. Affected products include: Getcomposer Composer, Tenable Tenable.Sc.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Composer is an open source dependency manager for the PHP language. In affected versions windows users running Composer to install untrusted dependencies are subject to command injection and should upgrade their composer version. Other OSs and WSL are not affected. The issue has been resolved in composer versions 1.10.23 and 2.1.9. There are no workarounds for this issue.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
OS command injection occurs when an application passes unsanitized user input directly into system shell commands.
Affected Products (CPE)NVD
Composer is a dependency manager for PHP. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, lo
Command injection in PHP Composer's Perforce VCS handler allows arbitrary local command execution with the privileges of
The tagDiv Composer WordPress plugin before 4.0 does not sanitise and escape a parameter before outputting it back in th
Composer is a dependency manager for PHP. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, lo
Composer is a dependency manager for the PHP programming language. Rated high severity (CVSS 8.8), this vulnerability is
Arbitrary code execution in MosaicML Composer arises when the library loads a model or resumption checkpoint, because ch
Arbitrary file write in Composer (the PHP dependency manager) before 2.2.29 and 2.10.2 allows a malicious package served
The tagDiv Composer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple shortcodes in all ver
Path traversal in Composer's binary installation flow allows a malicious PHP package to cause arbitrary host files to be
Improper input validation in the Drupal Composer contributed module (SA-contrib-2026-046) exposes sites to confidentiali
Path traversal in MosaicML Composer 0.32.1 and earlier allows an attacker who supplies a crafted checkpoint archive to w
Credential leakage in Composer PHP dependency manager exposes sensitive tokens - such as GitHub Personal Access Tokens e
Exploit-DB