What’s Vulnerable › Vulnerabilities

CVE-2026-55378: JS Recon: Command injection in PR Branch Checker workflow via untrusted pull request context values

• Severity: critical (CVSS 9.3 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-28 · updated 2026-09-09
• Weakness: CWE-78

Description

JS Recon is a JavaScript enumeration and SAST tool. From 1.2.1-beta.1 until 1.3.1-beta.2, the PR Branch Checker workflow in .github/workflows/pr_checker.yml places github.head_ref and github.event.pull_request.head.repo.full_name into BRANCH_NAME and SOURCE_REPO and interpolates those untrusted values into a shell gh pr comment command. A remote user who opens a pull request can use shell metacharacters in a branch or fork name to execute commands in the GitHub Actions runner with the workflow's GITHUB_TOKEN, which has pull-requests write permission. This issue is fixed in version 1.3.1-beta.2.

Affected products

• shriyanss js-recon: from 1.2.1-beta.1, < 1.3.1-beta.2

References

• https://github.com/js-recon/js-recon/commit/447876c4bfa9ec5bc98cbc65d7a3e5f889412491
• https://github.com/js-recon/js-recon/pull/121
• https://github.com/js-recon/js-recon/releases/tag/v1.3.1-beta.2
• https://github.com/js-recon/js-recon/security/advisories/GHSA-w9cj-mg3x-qjm4

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