CVE-2026-40261HIGH 8.8EPSS p74.8%
CVE-2026-40261CVE-2026-40261
getcomposer / composer
Description
Composer is a dependency manager for PHP. Versions 1.0 through 2.2.26 and 2.3 through 2.9.5 contain a command injection vulnerability in the Perforce::syncCodeBase() method, which appends the $sourceReference parameter to a shell command without proper escaping, and additionally in the Perforce::generateP4Command() method as in GHSA-wg36-wvj6-r67p / CVE-2026-40176, which interpolates user-supplied Perforce connection parameters (port, user, client) from the source url field without proper escaping. An attacker can inject arbitrary commands through crafted source reference or source url values containing shell metacharacters, even if Perforce is not installed. Unlike CVE-2026-40176, the source reference and url are provided as part of package metadata, meaning any compromised or malicious Composer repository can serve package metadata declaring perforce as a source type with malicious values. This vulnerability is exploitable when installing or updating dependencies from source, includi
Scoring
| CVSS 3.1 | 8.8 (HIGH) |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| EPSS | 1.69% probability of exploitation · percentile 74.8% · 2026-08-03T12:00:16Z |
| Published | 2026-04-15 |
| Last modified | 2026-07-15 |
Underlying weaknesses· 2
References
2
| Type | Target | Confidence | Tier |
|---|---|---|---|
| Weakness | Improper Input Validationcwe-20 | 0% | live |
| Weakness | Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')cwe-78 | 0% | live |
Related by meaning· 6
Nearest entities by semantic similarity across the cs-graph corpus.