Vowpal Wabbit is a machine learning system. The workflow .github/workflows/python_checks.yml embeds ${{ github.event.pull_request.title }} directly inside double-quoted bash strings in four separate steps across four jobs, each passing it as a CLI argument to the Python test script run_tests_model_gen_and_load.py. The shell interprets the expanded string before invoking Python, allowing an attacker to break out of the quotes and execute arbitrary commands on the runner. The pull_request trigger fires on PRs targeting any branch (branches: ['*']), with no additional access gate. This vulnerability is fixed by the 998e390e80a7e8192d7849b7784bc113dbd190ad commit.
History

Tue, 26 May 2026 17:00:00 +0000

Type Values Removed Values Added
Description Vowpal Wabbit is a machine learning system. The workflow .github/workflows/python_checks.yml embeds ${{ github.event.pull_request.title }} directly inside double-quoted bash strings in four separate steps across four jobs, each passing it as a CLI argument to the Python test script run_tests_model_gen_and_load.py. The shell interprets the expanded string before invoking Python, allowing an attacker to break out of the quotes and execute arbitrary commands on the runner. The pull_request trigger fires on PRs targeting any branch (branches: ['*']), with no additional access gate. This vulnerability is fixed by the 998e390e80a7e8192d7849b7784bc113dbd190ad commit.
Title Vowpal Wabbit: Shell injection via crafted PR title in python_checks.yml allows arbitrary command execution on CI runner
Weaknesses CWE-1336
CWE-78
References
Metrics cvssV3_1

{'score': 5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-26T15:49:17.951Z

Reserved: 2026-05-07T18:04:17.308Z

Link: CVE-2026-44723

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-26T17:16:46.680

Modified: 2026-05-26T17:16:46.680

Link: CVE-2026-44723

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-26T18:45:13Z