Skip to content
Fencer Vulns
high 7.5

CVE-2026-45793 json

Composer: Github Actions issued GITHUB_TOKEN disclosure in GitHub Actions logs

published 2026-05-19 5 mo ago modified 2026-07-20 3 mo ago also BIT-composer-2026-45793 , EUVD-2026-44723 , GHSA-f9f8-rm49-7jv2

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits
0
none known

Summary

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.

Patch / fix

  • packagist composer/composer 1.10.28, 2.2.28, 2.9.8
  • bitnami composer 1.10.28, 2.2.28, 2.9.8
  • getcomposer composer 1.10.28, 2.2.28, 2.9.8
  • composer Debian 12 2.5.5-1+deb12u5
  • composer Debian 13 2.8.8-1+deb13u3
  • composer Debian 14 2.10.0-1

debian advisories DEBIAN-CVE-2026-45793

  • php-composer2 SLES for SAP applications 16.0, SLES 16.0 2.8.9-160000.6.1
  • php-composer2 SLE Module for Web and Scripting 15 SP7 2.6.4-150600.3.23.1
  • php-composer2 SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 2.2.30-150400.3.21.1
  • php-composer2 SLES 16.0, SLES for SAP applications 16.0 2.8.9-160000.4.1
  • php-composer2 SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Web and Scripting 15 SP7 2.6.4-150600.3.12.1

suse advisories SUSE-SU-2026:23943-1SUSE-SU-2026:4288-1SUSE-SU-2026:4283-1SUSE-SU-2026:23116-1SUSE-SU-2026:23138-1SUSE-SU-2026:3105-1

  • php-composer2 openSUSE Leap 16.0 2.8.9-160000.6.1
  • php-composer2 openSUSE Leap 16.0 2.8.9-160000.4.1
  • php-composer2 openSUSE Tumbleweed 2.10.2-2.1

opensuse advisories openSUSE-SU-2026:21970-1openSUSE-SU-2026:21520-1openSUSE-SU-2026:11300-1

  • composer Alpine 3.24 2.9.8-r0

alpine advisories ALPINE-CVE-2026-45793

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-45793 updated cvss 7.5

composer/composer: Composer: Information disclosure of GitHub OAuth tokens via improper validation

  • Red Hat Hardened Images composer
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

1.02% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
packagist composer/composer
>=2.3.0, <2.9.8
>=2.0.0, <2.2.28
>=1.0, <1.10.28
2.9.8
2.2.28
1.10.28
bitnami composer
>=1.0.0, <1.10.28
>=2.0.0, <2.2.28
>=2.3.0, <2.9.8
1.10.28
2.2.28
2.9.8

Affected products

  • composer composer

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.