What is the CVSS score of CVE-2026-44723?

CVE-2026-44723 has a CVSS 3.1 base score of 5.0 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N. EPSS exploitation probability: 0.0%.

Is there a patch available for CVE-2026-44723?

Yes, a patch is available for CVE-2026-44723. Update the affected software to the latest version immediately.

Vowpal Wabbit CVE-2026-44723

EUVD-2026-31902 MEDIUM

OS Command Injection (CWE-78)

2026-05-26 GitHub_M

Python Command Injection Vowpal Wabbit

5.0

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

5.0 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

None

Availability

None

Lifecycle Timeline

Source Code Evidence Fetched

Jun 08, 2026 - 12:33 vuln.today

Analysis Generated

Jun 08, 2026 - 12:33 vuln.today

Patch available

May 26, 2026 - 18:02 EUVD

DescriptionGitHub Advisory

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.

AnalysisAI

{{ github.event.pull_request.title }} directly into bash double-quoted strings across four steps in four separate jobs, enabling shell escape via crafted PR title content. No public exploit has been identified and EPSS stands at 0.03% (10th percentile), though the supply-chain nature of this CI-targeting vulnerability means successful exploitation could expose repository secrets and runner tokens.

Technical ContextAI

This is a GitHub Actions expression injection vulnerability rooted in CWE-78 (OS Command Injection). GitHub Actions workflows evaluate ${{ }} expressions before the shell runtime executes the run: step script, meaning the PR title string is substituted directly into the bash script text. When placed inside double-quoted bash arguments - as seen in the four affected steps passing --skip_pr_tests '${{ github.event.pull_request.title }}' - an attacker can include shell metacharacters (e.g., "; malicious_cmd; ") to break out of the quoted context and inject arbitrary commands. The workflow uses a pull_request trigger scoped to all branches (branches: ['*']), so any fork-and-PR submission activates the vulnerable jobs. The fix, confirmed in commit 998e390e80a7e8192d7849b7784bc113dbd190ad, moves the PR title into an environment variable (PR_TITLE: ${{ github.event.pull_request.title }}) which is then referenced as $PR_TITLE in the shell - this correctly prevents expression interpolation from being interpreted as shell syntax. The affected CPE is cpe:2.3:a:vowpalwabbit:vowpal_wabbit:*:*:*:*:*:*:*:*.

RemediationAI

Upstream fix available via commit 998e390e80a7e8192d7849b7784bc113dbd190ad; a released tagged version containing this fix has not been independently confirmed beyond the commit reference. Repository maintainers and forks running this workflow should apply the fix by updating .github/workflows/python_checks.yml to pass ${{ github.event.pull_request.title }} as an environment variable (e.g., env: PR_TITLE: ${{ github.event.pull_request.title }}) and reference $PR_TITLE in the shell run step rather than embedding the expression directly. As a compensating control prior to patching, maintainers can restrict the pull_request trigger to require the pull_request_target event type combined with explicit approval gates, preventing untrusted fork PRs from executing workflows with access to repository secrets - note this changes the workflow trigger model and may affect CI coverage for external contributors. The fix commit and advisory are at https://github.com/VowpalWabbit/vowpal_wabbit/commit/998e390e80a7e8192d7849b7784bc113dbd190ad and https://github.com/VowpalWabbit/vowpal_wabbit/security/advisories/GHSA-cg2g-xgg7-3xxq respectively.