llhttp vulnerable to HTTP request smugglingGHSA-cggh-pq45-6h9x
HIGHGHSA-cggh-pq45-6h9x is a high-severity (CVSS 7.5) vulnerability in llhttp. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for llhttp — see the affected versions and patch details below.
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-cggh-pq45-6h9x.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
llhttpnpmDescription
The llhttp parser in the http module in Node v20.2.0 does not strictly use the CRLF sequence to delimit HTTP requests. This can lead to HTTP Request Smuggling (HRS).
The CR character (without LF) is sufficient to delimit HTTP header fields in the llhttp parser. According to RFC7230 section 3, only the CRLF sequence should delimit each header-field. This impacts all Node.js active versions: v16, v18, and, v20
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | llhttp | all versions | 8.1.1npm install llhttp@8.1.1 |
Affected Products
fedorafedoraprojectnode.jsnodejsResearch 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 llhttp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update llhttp to 8.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cggh-pq45-6h9x 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.
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.
The vulnerability is in the llhttp parsing not using the CRLF sequence which violates the HTTP/1.1 specification, which mandates CRLF as the delimiter. While this might result in request smuggling, the added complexity of creating a valid malformed delimited request and having it reach the intended target and then…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | nodejs:18-8080020230718130356.63b34585 | RHSA-2023:4536 |
| Red Hat Enterprise Linux 8 | nodejs:16-8080020230718141521.63b34585 | RHSA-2023:4537 |
| Red Hat Enterprise Linux 8.6 Extended Update Support | nodejs:16-8060020230906023909.ad008a3a | RHSA-2023:5361 |
| Red Hat Enterprise Linux 9 | nodejs:18-9020020230717125503.rhel9 | RHSA-2023:4330 |
| Red Hat Enterprise Linux 9 | nodejs-1:16.20.1-1.el9_2 | RHSA-2023:4331 |
| Red Hat Enterprise Linux 9.0 Extended Update Support | nodejs-1:16.20.2-1.el9_0 | RHSA-2023:5533 |
Frequently Asked Questions
Is GHSA-cggh-pq45-6h9x in your dependencies?
Find it across npm, including transitive dependencies.