CVE-2025-23167

nodejs: Improper HTTP Header Termination in Node.js 20 Enables Request Smuggling

Severity Score

6.5

*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Attend

*SSVC

Descriptions

A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using `\r
\rX` instead of the required `\r
\r
`.
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.

A flaw was found in the HTTP parser of Node.js. This vulnerability allows attackers to perform request smuggling and bypass proxy-based access controls via improperly terminated HTTP/1 headers using \r
\rX instead of the standard \r
\r
.

A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using `\r
\rX` instead of the required `\r
\r
`. 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.

This update for nodejs20 fixes the following issues. Improper error handling in async cryptographic operations crashes process. Improper HTTP header block termination in llhttp. Add missing call to uv_fs_req_cleanup. Other bug fixes.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:Attend

Exploitation

None

Automatable

Yes

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2025-01-12 CVE Reserved
2025-05-19 CVE Published
2025-05-27 CVE Updated
2025-07-05 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CAPEC

References (3)

URL	Tag	Source
https://nodejs.org/en/blog/vulnerability/may-2025-security-releases

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://access.redhat.com/security/cve/CVE-2025-23167	2025-06-04
https://bugzilla.redhat.com/show_bug.cgi?id=2367167	2025-06-04

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 4.0 < 4.* Search vendor "Nodejs" for product "Node" and version " >= 4.0 < 4.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 5.0 < 5.* Search vendor "Nodejs" for product "Node" and version " >= 5.0 < 5.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 6.0 < 6.* Search vendor "Nodejs" for product "Node" and version " >= 6.0 < 6.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 7.0 < 7.* Search vendor "Nodejs" for product "Node" and version " >= 7.0 < 7.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 8.0 < 8.* Search vendor "Nodejs" for product "Node" and version " >= 8.0 < 8.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 9.0 < 9.* Search vendor "Nodejs" for product "Node" and version " >= 9.0 < 9.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 10.0 < 10.* Search vendor "Nodejs" for product "Node" and version " >= 10.0 < 10.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 11.0 < 11.* Search vendor "Nodejs" for product "Node" and version " >= 11.0 < 11.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 12.0 < 12.* Search vendor "Nodejs" for product "Node" and version " >= 12.0 < 12.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 13.0 < 13.* Search vendor "Nodejs" for product "Node" and version " >= 13.0 < 13.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 14.0 < 14.* Search vendor "Nodejs" for product "Node" and version " >= 14.0 < 14.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 15.0 < 15.* Search vendor "Nodejs" for product "Node" and version " >= 15.0 < 15.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 16.0 < 16.* Search vendor "Nodejs" for product "Node" and version " >= 16.0 < 16.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 17.0 < 17.* Search vendor "Nodejs" for product "Node" and version " >= 17.0 < 17.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 18.0 < 18.* Search vendor "Nodejs" for product "Node" and version " >= 18.0 < 18.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 19.0 < 19.* Search vendor "Nodejs" for product "Node" and version " >= 19.0 < 19.*"		en		Affected
Nodejs Search vendor "Nodejs"		Node Search vendor "Nodejs" for product "Node"				>= 20.0.0 <= 20.19.1 Search vendor "Nodejs" for product "Node" and version " >= 20.0.0 <= 20.19.1"		en		Affected