CVE-2026-45793 | Composer: Github Actions issued GITHUB_TOKEN disclosure in GitHub Actions logs

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.

Published: 2026-07-15 Last update: 2026-07-15 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-45793 is rated Moderate Risk (48.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.80%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-45793

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-21 0.52% 0.80% +0.28%
2 2026-07-16 0.06% 0.52% +0.46%
3 2026-06-12 — 0.06% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-45793

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-45793

GitHub Security Advisory for CVE-2026-45793

GHSA-f9f8-rm49-7jv2 · Severity: high · Ecosystem: composer — Github Actions issued GITHUB_TOKEN disclosure in GitHub Actions logs

OS Trackers for CVE-2026-45793

vendor priority summary link
debian not yet assigned CVE-2026-45793 not yet assigned priority: Debian including 1 source packages (composer), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2026-45793
suse medium CVE-2026-45793 severity moderate: SUSE including 1 source package names (php-composer2-2.6.4-150600.3.12.1), 3 product×package rows across 3 product lines (SUSE Linux Enterprise Module for Web and Scripting 15 SP7, SUSE Linux Enterprise Server 15 SP6-LTSS, SUSE Linux Enterprise Server for SAP Applications 15 SP6): First Fixed 3. https://www.suse.com/security/cve/CVE-2026-45793/
ubuntu medium CVE-2026-45793 medium priority: Ubuntu including 1 source packages (composer), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): not-affected 4, needs-triage 2, released 1. https://ubuntu.com/security/CVE-2026-45793

Affected software / configurations for CVE-2026-45793

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-45793

cvelogic Threat Intelligence