CVE-2026-45793

HIGH 7.5

Composer: Github Actions issued GITHUB_TOKEN disclosure in GitHub Actions logs

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-200
Vendor	composer
Product	composer
Published	Jul 15, 2026
Last Updated	Jul 15, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Affected Versions

composer / composer

>= 1.0, < 1.10.28 >= 2.0.0, < 2.2.28 >= 2.3.0, < 2.9.8

References

NVD ↗ CVE.org ↗ EPSS Data ↗