Information disclosure in Composer

CVE-2026-59947

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 P…

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

  • Composer — versions >= 1.0, < 2.2.29, >= 2.3.0, < 2.10.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-59947?
CVE-2026-59947 is a medium-severity vulnerability in Composer, classified under Insertion of Sensitive Information into Log File. CVSS score: 4.7/10. Published 2026-07-08.
How severe is CVE-2026-59947?
Medium severity. CVSS v3 base score is 4.7 out of 10.