GHSA-rxc4-3w6r-4v47 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in vllm. A fix is available for vllm — see the affected versions and patch details below.
vllm API endpoints vulnerable to Denial of Service Attacks
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-rxc4-3w6r-4v47.
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
GHSA-rxc4-3w6r-4v47 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 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
vllmReal-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
Summary
A Denial of Service (DoS) vulnerability can be triggered by sending a single HTTP GET request with an extremely large header to an HTTP endpoint. This results in server memory exhaustion, potentially leading to a crash or unresponsiveness. The attack does not require authentication, making it exploitable by any remote user.
Details
The vulnerability leverages the abuse of HTTP headers. By setting a header such as X-Forwarded-For to a very large value like ("A" * 5_800_000_000), the server's HTTP parser or application logic may attempt to load the entire request into memory, overwhelming system resources.
Impact
What kind of vulnerability is it? Who is impacted? Type of vulnerability: Denial of Service (DoS)
Resolution
Upgrade to a version of vLLM that includes appropriate HTTP limits by deafult, or use a proxy in front of vLLM which provides protection against this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | vllm | ≥ 0.1.0&&< 0.10.1.1 | 0.10.1.1pip install --upgrade 'vllm==0.10.1.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vllm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update vllm to 0.10.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-rxc4-3w6r-4v47 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-rxc4-3w6r-4v47 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-rxc4-3w6r-4v47. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability is considered Important rather than just Moderate because it enables a complete denial of service with minimal effort from a remote, unauthenticated attacker. Unlike moderate flaws that might require specific conditions, partial access, or complex exploitation chains, here a single oversized HTTP…
Until a fix is available, the risk can be reduced by running vLLM behind a reverse proxy such as Nginx, Envoy, or HAProxy with strict header size limits, ensuring that oversized requests are dropped before reaching the service. Additional safeguards like container or VM resource limits and traffic monitoring can help contain the impact, but upgrading to the patched release remains the definitive solution.Source: Red Hat security advisory for GHSA-rxc4-3w6r-4v47 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux AI 1.5 | rhelai1/instructlab-intel-rhel9:1.5.4-1761050413 | RHSA-2025:19421 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/bootc-intel-rhel9:1.5.4-1761060689 | RHSA-2025:19422 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/instructlab-nvidia-rhel9:1.5.4-1761220254 | RHSA-2025:19423 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/bootc-azure-amd-rhel9:1.5.4-1761073793 | RHSA-2025:19424 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/instructlab-amd-rhel9:1.5.4-1761043227 | RHSA-2025:19425 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/bootc-gcp-nvidia-rhel9:1.5.4-1761236079 | RHSA-2025:19426 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/bootc-amd-rhel9:1.5.4-1761064179 | RHSA-2025:19427 |
| Red Hat Enterprise Linux AI 1.5 | rhelai1/bootc-nvidia-rhel9:1.5.4-1761228838 | RHSA-2025:19428 |
Frequently Asked Questions
Is GHSA-rxc4-3w6r-4v47 in your dependencies?
O3 Security finds GHSA-rxc4-3w6r-4v47 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.