CVE-2026-59948

HIGH

Composer: Arbitrary file write outside vendor via malicious transitive package name

Title source: cna
STIX 2.1

Description

Composer is a dependency Manager for the PHP language. Prior to 2.2.29 and 2.10.2, a maliciously crafted package from an untrusted repository other than Packagist.org or Private Packagist can cause Composer to write attacker-controlled files outside the vendor directory and outside the project during install or update by using an invalid package name that is not correctly validated before dependency-resolution results are written or installed. This issue is fixed in versions 2.2.29 and 2.10.2.

Scores

CVSS v3 7.0
EPSS 0.0014
EPSS Percentile 3.6%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-22 CWE-787
Status published
Products (4)
composer/composer 1.0.0 - 2.2.29Packagist
composer/composer 2.3.0 - 2.10.2Packagist
composer/composer >= 1.0, < 2.2.29
composer/composer >= 2.3.0, < 2.10.2
Published Jul 08, 2026
Tracked Since Jul 09, 2026