CVE-2026-59947mediumCWE-532

CVE-2026-59947: medium-severity vulnerability in composer

Composer: URL-embedded HTTP-Basic username leaks to verbose logs (GitHub PAT exposure)

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4.7epss 0.1%
Composer is a dependency Manager for the PHP language. Prior to 2.2.29 and 2.10.2, when Composer is run with -vvv debug verbosity, it could print a credential embedded in the username slot of a repository or package URL, such as a GitHub Personal Access Token in https://TOKEN@host/, to debug output because AuthHelper, Url::sanitize, and ProcessExecutor did not sanitize username-only URL credentials. This issue is fixed in versions 2.2.29 and 2.10.2.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected products
composer · composer
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