SB2026110645 - Multiple vulnerabilities in composer

Description

This security bulletin contains information about 2 vulnerabilities.

1) Information disclosure (CVE-ID: N/A)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: 5.6 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows an unauthenticated remote attacker to obtain repository credentials from a shared composer.lock file.

The vulnerability exists due to Composer copying options.http.header values into the lock file when downloading package archives under a Composer-type repository's URL, even when the repository is configured outside the project in global config.json. An unauthenticated remote attacker can read these credentials if a developer generates and shares the lock file with unauthorized readers.

2) Path traversal (CVE-ID: N/A)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows an unauthenticated local attacker to delete directories and write package files outside vendor/ with the privileges of the user running Composer.

The vulnerability exists due to missing validation of package names containing .. path segments in vendor/composer/installed.json during installation or reinstallation. An unauthenticated local attacker can tamper with this file before a victim runs Composer, triggering directory deletion during installation or reinstallation and file writes during reinstallation.

Remediation

Install update from vendor's website.

References

• https://github.com/composer/composer/security/advisories/GHSA-fm2w-xgf2-f9fh
• https://github.com/composer/composer/security/advisories/GHSA-c968-33g3-wh7p