CVE-2026-59947
Composer: URL-embedded HTTP-Basic username leaks to verbose logs (GitHub PAT exposure)
4.7
MEDIUM
CVSS 3.1
EPSS 0.11%
Description
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.
How to fix CVE-2026-59947
To remediate CVE-2026-59947, upgrade the affected package to a fixed version below.
- —upgrade to 2.2.29 or later
- —upgrade to 2.10.2 or later
Is CVE-2026-59947 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- >= 1.0.0, < 2.2.29, >= 2.3.0, < 2.10.2
- >= 2.3.0, < 2.10.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |