CVE-2026-84361
Description
A flaw was found in Composer. A malicious dependency package from a custom Composer repository or an untrusted composer.lock file could exploit a vulnerability in how Composer handles Perforce source URLs. By setting source.type to perforce and source.url to an rsh: or jsh: P4PORT value, an attacker could cause the Perforce p4 client to execute arbitrary local commands. This could lead to arbitrary code execution with the privileges of the user or continuous integration (CI) account running Composer.
Mitigation
To mitigate this issue, avoid installing the Perforce `p4` client on systems where Composer is used, unless explicitly required. Additionally, ensure that Composer only processes dependencies from trusted repositories and `composer.lock` files to prevent the introduction of malicious `source.url` values.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.3 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Confidentiality,Integrity,Availability,Non-Repudiation
Technical Impact: Execute Unauthorized Code or Commands; DoS: Crash, Exit, or Restart; Read Files or Directories; Modify Files or Directories; Read Application Data; Modify Application Data; Hide Activities
Attackers could execute unauthorized operating system commands, which could then be used to disable the product, or read and modify data for which the attacker does not have permissions to access directly. Since the targeted application is directly executing the commands instead of the attacker, any malicious activities may appear to come from the application or the application's owner.
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