CVE-2023-30589

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-07-01 · updated 2026-10-08

Description

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 products

Fedoraproject Fedora: 37, 38
Node.js: from 16.0.0 before 16.20.1; from 18.0.0 before 18.16.1; from 20.0.0 before 20.3.1 — fixed in 16.20.1, 18.16.1, 20.3.1

How to fix

Upgrade to a fixed version: Node.js 16.20.1, 18.16.1, 20.3.1. Check the vendor advisory for mitigations.

References

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