Vulnerability in Nodejs Node
CVE-2025-23167
A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using `\r\n\rX` instead of the required `\r\n\r\n`. This inconsistency enables request smuggling, allowing attackers to bypass proxy-based access controls and submit unauthorized requests. The issue was resolved by upgrading `llhttp` to version 9, which enforces correct header termination. Impact: * This vulnerability affects only Node.js 20.x users prior to the `llhttp` v9 upgrade.
Vulnerability class: HTTP Request Smuggling
EPSS: 0.005 (37.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
Affected products
- Nodejs Node — versions 4.0, 5.0, 6.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
Frequently asked questions
- What is CVE-2025-23167?
- CVE-2025-23167 is a medium-severity vulnerability in Nodejs Node, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 6.5/10. Published 2025-05-19.
- How severe is CVE-2025-23167?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2025-23167 known to be exploited?
- 6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.