RCE in Vowpalwabbit Vowpal Wabbit
CVE-2026-44723
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.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.006 (45.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001
Affected products
- Vowpalwabbit Vowpal Wabbit — versions < 998e390e80a7e8192d7849b7784bc113dbd190ad
Weakness classification (CWE)
References
- github.com/VowpalWabbit/vowpal_wabbit/security/advisories/GHSA-cg2g-xgg7-3xxq (Exploit, Mitigation, Vendor Advisory)
- github.com/VowpalWabbit/vowpal_wabbit/commit/998e390e80a7e8192d7849b7784bc113db… (Patch)
Frequently asked questions
- What is CVE-2026-44723?
- CVE-2026-44723 is a medium-severity vulnerability in Vowpalwabbit Vowpal Wabbit, classified under OS Command Injection. CVSS score: 5.0/10. Published 2026-05-26.
- How severe is CVE-2026-44723?
- Medium severity. CVSS v3 base score is 5.0 out of 10.