by Kastro
Paper/Archive/CVE-2026-44723

CVE-2026-44723

VowpalWabbit vowpal_wabbit — Vowpal Wabbit: Shell injection via crafted PR title in python_checks.yml allows arbitrary command execution on CI runner

EPSS 0.5%public exploitCVSS 9.9
critical.is priorityof 100
48
CVSS 9.9 (NVD)9.9 / 10 × 3029.7Not in CISA KEV+300.0EPSS percentile 40.6.406 × 208.1Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
vowpal_wabbit< 998e390e80a7e8192d7849b7784bc113dbd190ad–CNA

Scores by source

NVD9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
GitHub_M (CNA)5.0CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: partial

References

exploitgithub.com/VowpalWabbit/vowpal_wabbit/security/advisories/GHSA-cg2g-xgg7-3xxqrefgithub.com/VowpalWabbit/vowpal_wabbit/commit/998e390e80a7e8192d7849b7784bc113dbd190ad