Information Exposure Affecting composer package, versions <2.5.5-1+deb12u5


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
1.02% (61st percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-DEBIAN12-COMPOSER-16743193
  • published18 May 2026
  • disclosed15 Jul 2026

Introduced: 18 May 2026

CVE-2026-45793  (opens in a new tab)
CWE-200  (opens in a new tab)

How to fix?

Upgrade Debian:12 composer to version 2.5.5-1+deb12u5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream composer package and not the composer package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

Composer is a dependency Manager for the PHP language. Prior to 1.10.28, 2.2.28, and 2.9.8, Composer\IO\BaseIO::loadConfiguration() validates GitHub OAuth tokens with the regex ^[.A-Za-z0-9_]+$ and interpolates rejected tokens into an UnexpectedValueException; GitHub Actions GITHUB_TOKEN values using the ghs_<id>_<base64url-JWT> format can contain -, fail validation, and be disclosed to stderr or CI logs. This issue is fixed in versions 1.10.28, 2.2.28, and 2.9.8.

CVSS Base Scores

version 3.1