CVE-2026-84361

7.7 HIGH 0.5% exploit odds Fix listed Injection Web app

What it is

Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client was installed and Composer installed the package from source through composer install or composer update, including --prefer-source, Composer\Util\Perforce passed the address to p4 without validation, causing p4 to run a local command with the privileges of the user or CI account. Packagist.org does not permit Perforce source metadata. This issue is fixed in versions 2.2.30 and 2.10.3.

At a glance

Exploitability: Can be exploited over the network without logging in, but needs a user to act. High risk of data exposure, data tampering, service disruption.
Exploit odds: 0.5% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-09-01 21:18 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-09-09 21:09 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.5% in the next 30 days (EPSS).
Severity: 7.7 HIGH (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2026-09-01 21:18 UTC
Last modified: 2026-09-09 21:09 UTC
Exploit probability: 0.5% · EPSS, next 30 days
Weakness: CWE-78 · OS command injection
Record status: Deferred

Attack profile CVSS 4.0 · 7.7

Attack vector: Network
Complexity: Low
Attack requirements: Present
Privileges needed: None
User interaction: Passive
Confidentiality: High
Integrity: High
Availability: High

Raw vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-84361.md and follow it. Check whether this project is affected by CVE-2026-84361. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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Fix and advisories

References

NVD record · CVE.org record