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 ...
CVE-2025-23167 is a vulnerability in Node. js 20's HTTP parser where HTTP/1 headers can be improperly terminated using '\r\n\rX' instead of the required '\r\n\r\n'. This inconsistency enables HTTP request smuggling, potentially allowing attackers to bypass proxy-based access controls and submit unauthorized requests. The vulnerability affects certain Microsoft products including Azure Linux versions 2. 0 and 3. 0. No CVSS score or patch information is currently available, and there are no known exploits in the wild at this time.
AI Analysis
Technical Summary
This vulnerability arises from a flaw in Node.js 20's HTTP parser that permits improper termination of HTTP/1 headers using a sequence '\r\n\rX' rather than the mandated '\r\n\r\n'. This deviation from the HTTP specification can be exploited for HTTP request smuggling attacks, which may allow attackers to bypass proxy-based access controls and submit unauthorized requests. The affected products include Microsoft Azure Linux versions 2.0 and 3.0. The vulnerability is tracked as CVE-2025-23167 and is categorized under CWE-444 (Improper Resource Shutdown or Release). No patch or official remediation guidance has been provided by Microsoft Security Response Center at this time.
Potential Impact
The vulnerability enables HTTP request smuggling by allowing improper termination of HTTP/1 headers, which can lead to bypassing proxy-based access controls. This could result in unauthorized requests being processed by backend servers. However, there are currently no known exploits in the wild, and the full extent of impact depends on the deployment environment and proxy configurations.
Mitigation Recommendations
Patch status is not yet confirmed — check the Microsoft Security Response Center advisory for current remediation guidance. Until an official fix is available, organizations should review their proxy and HTTP handling configurations to detect and mitigate potential request smuggling attempts. No vendor advisory or patch links are currently provided, so monitoring official Microsoft channels for updates is recommended.
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 ...
Description
CVE-2025-23167 is a vulnerability in Node. js 20's HTTP parser where HTTP/1 headers can be improperly terminated using '\r\n\rX' instead of the required '\r\n\r\n'. This inconsistency enables HTTP request smuggling, potentially allowing attackers to bypass proxy-based access controls and submit unauthorized requests. The vulnerability affects certain Microsoft products including Azure Linux versions 2. 0 and 3. 0. No CVSS score or patch information is currently available, and there are no known exploits in the wild at this time.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability arises from a flaw in Node.js 20's HTTP parser that permits improper termination of HTTP/1 headers using a sequence '\r\n\rX' rather than the mandated '\r\n\r\n'. This deviation from the HTTP specification can be exploited for HTTP request smuggling attacks, which may allow attackers to bypass proxy-based access controls and submit unauthorized requests. The affected products include Microsoft Azure Linux versions 2.0 and 3.0. The vulnerability is tracked as CVE-2025-23167 and is categorized under CWE-444 (Improper Resource Shutdown or Release). No patch or official remediation guidance has been provided by Microsoft Security Response Center at this time.
Potential Impact
The vulnerability enables HTTP request smuggling by allowing improper termination of HTTP/1 headers, which can lead to bypassing proxy-based access controls. This could result in unauthorized requests being processed by backend servers. However, there are currently no known exploits in the wild, and the full extent of impact depends on the deployment environment and proxy configurations.
Mitigation Recommendations
Patch status is not yet confirmed — check the Microsoft Security Response Center advisory for current remediation guidance. Until an official fix is available, organizations should review their proxy and HTTP handling configurations to detect and mitigate potential request smuggling attempts. No vendor advisory or patch links are currently provided, so monitoring official Microsoft channels for updates is recommended.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_vex
- Csaf Version
- 2.0
- Publisher
- Microsoft Security Response Center
- Advisory Id
- msrc_CVE-2025-23167
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a1ca153e29bf47b505e07d7
Added to database: 5/31/2026, 9:00:03 PM
Last enriched: 5/31/2026, 9:00:57 PM
Last updated: 6/2/2026, 4:59:55 AM
Views: 7
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