NVD / CVE Program· CNA GitHub_M

CVE-2026-84361: Composer: Perforce source URL permits P4PORT `rsh:` command execution

Noroxi assessment

Priority: Monitor (action score 30/100)

Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
Probability of exploitation in the next 30 days: 0.50% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No special conditions are required; it is repeatable.
Fixed version: composer (Alpine:v3.24) 2.10.3-r0; composer (Debian:14) 2.10.3-1; php-composer2 (openSUSE:Leap 16.0) 2.8.9-160000.5.1.

Low priority for now. Upgrade to composer (Alpine:v3.24) 2.10.3-r0; composer (Debian:14) 2.10.3-1; php-composer2 (openSUSE:Leap 16.0) 2.8.9-160000.5.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

HighCVSS 7.7 · v4.0—Proof of concept Fix available

Published: Sep 1, 2026
Updated: Sep 9, 2026
EPSS: 0.5% · 43th percentile
CWE: CWE-78

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.7 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.5%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 7.7; NVD has not scored this yet; the score shown is the CNA’s.

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
Proof of concept exists, no weaponized module
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

composer composer
- >= 1.0, < 2.2.30, >= 2.3.0, < 2.10.3affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Alpine:v3.24	composer	before 2.10.3-r0	2.10.3-r0
Debian:12	composer	from 0	—
Debian:14	composer	before 2.10.3-1	2.10.3-1
openSUSE:Leap 16.0	php-composer2	before 2.8.9-160000.5.1	2.8.9-160000.5.1
openSUSE:Tumbleweed	php-composer2	before 2.10.3-2.1	2.10.3-2.1
Packagist	composer/composer	from 1.0 · before 2.2.30	2.2.30
Packagist	composer/composer	from 2.3.0 · before 2.10.3	2.10.3
Red Hat:hummingbird:1	composer	before 0:2.10.3-1.hum1	0:2.10.3-1.hum1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	php-composer2	before 2.2.30-150400.3.21.1	2.2.30-150400.3.21.1
SUSE:Linux Enterprise Module for Web and Scripting 15 SP7	php-composer2	before 2.6.4-150600.3.18.1	2.6.4-150600.3.18.1
SUSE:Linux Enterprise Server 16.0	php-composer2	before 2.8.9-160000.5.1	2.8.9-160000.5.1

Same product

composer: all records

Other highest-scoring records for the same primary product.

CVE-2024-35242Composer vulnerable to command injection via malicious git/hg branch names
36Monitor
CVE-2024-35241Composer vulnerable to command injection via malicious git branch name
35Monitor
CVE-2026-45793Composer: Github Actions issued GITHUB_TOKEN disclosure in GitHub Actions logs
30Monitor

Published before and after this one in the same product

← EarlierCVE-2026-59947Jul 8, 2026 · Composer: URL-embedded HTTP-Basic username leaks to verbose logs (GitHub PAT exposure)
18Monitor
← EarlierCVE-2026-59948Jul 8, 2026 · Composer: Arbitrary file write outside vendor via malicious transitive package name
28Monitor
Later →CVE-2026-59944Sep 16, 2026 · Composer: CVE-2026-59946 fix bypass via symlinked package bin path
24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
alpine:composer	2.10.3-r0 · Alpine:v3.24	Package registry (OSV)
debian:composer	2.10.3-1 · Debian:14	Package registry (OSV)
opensuse:php-composer2	2.10.3-2.1 · openSUSE:Tumbleweed	Package registry (OSV)
Packagist:composer/composer	2.10.3	Package registry (OSV)
Packagist:composer/composer	2.2.30	Package registry (OSV)
red hat:composer	0:2.10.3-1.hum1 · Red Hat:hummingbird:1	Package registry (OSV)
suse:php-composer2	2.8.9-160000.5.1 · SUSE:Linux Enterprise Server 16.0	Package registry (OSV)

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Proof-of-concept repository on GitHub	stars:0	2026-09-02

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

PublishedSep 1, 2026
First PoCSep 2, 2026same day
TodayNov 9, 2026+69 d

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: P
Scope: X

Weakness class (CWE)

CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CVSS 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

nvd-secondary

Root cause

User input is inserted as text into a shell command. The shell may interpret special characters in the input as part of the command.

The bug in code

The whole CWE-78 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const host = req.body.host;
2exec("ping -c 1 " + host, onResult);

Fixed

1const host = req.body.host;
2if (!/^[a-z0-9.-]{1,253}$/i.test(host)) return res.sendStatus(400);
3execFile("ping", ["-c", "1", host], onResult);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

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Change log

Fix✗ → ✓Sep 28, 2026, 10:46 PM UTC

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References

github.com/composer/composer/commit/0aac50528e83ed635cf788333635897469440220

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records