CVE-2023-6021 — ray
CRITICALCVE-2023-6021 is a critical-severity (CVSS 9.3) CWE-29 vulnerability in ray. 1 public exploit reference exists, so weaponization risk is real. A fix is available for ray — see the affected versions and patch details below.
Ray Path Traversal vulnerability
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-6021.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-6021 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
rayReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
LFI in Ray's log API endpoint allows attackers to read any file on the server without authentication. The issue is fixed in version 2.8.1+. Ray maintainers' response can be found here: https://www.anyscale.com/blog/update-on-ray-cves-cve-2023-6019-cve-2023-6020-cve-2023-6021-cve-2023-48022-cve-2023-48023
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | ray | all versions | 2.8.1pip install --upgrade 'ray==2.8.1' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ray, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ray to 2.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-6021 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-6021 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-6021. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2023-6021
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2023-6021 -u https://target- Template
- Ray API - Local File Inclusion
- Severity
- high
- Impact
- Unauthenticated attackers can read any file on the server via the log API endpoint, potentially accessing sensitive configuration files, credentials, and application data.
- Remediation
- Update Ray to a patched version that properly validates file paths in the logs endpoint.
Template by ProjectDiscovery nuclei-templates (byt3bl33d3r), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2023-6021 in your dependencies?
O3 Security finds CVE-2023-6021 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.