CVE-2026-45793

CVE-2026-45793 affects Composer (PHP dependency manager). Prior to 1.10.28, 2.2.28, and 2.9.8, Composer\IO\BaseIO::loadConfiguration() validated GitHub tokens with ^[.A-Za-z0-9_]+$ and interpolated rejected tokens into an UnexpectedValueException. GitHub Actions GITHUB_TOKEN values formatted as g...