CVE-2026-21712: Vulnerability in nodejs node
A flaw in Node.js URL processing causes an assertion failure in native code when `url.format()` is called with a malformed internationalized domain name (IDN) containing invalid characters, crashing the Node.js process.
AI Analysis
Technical Summary
This vulnerability in Node.js arises from improper handling of malformed internationalized domain names (IDNs) in the url.format() function. When url.format() is called with an IDN containing invalid characters, it triggers an assertion failure in native code, causing the Node.js process to crash. The flaw is classified under CWE-20 (Improper Input Validation) and affects Node.js versions 24.14.0 and 25.8.1. The CVSS 3.0 base score is 5.7, reflecting a medium severity denial of service impact with network attack vector, low attack complexity, requiring privileges and user interaction.
Potential Impact
The vulnerability causes a denial of service by crashing the Node.js process when processing malformed IDNs via url.format(). There is no impact on confidentiality or integrity. No known active exploitation has been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or malformed internationalized domain names with url.format() in affected Node.js versions. Monitor official Node.js channels for updates and patches addressing this issue.
CVE-2026-21712: Vulnerability in nodejs node
Description
A flaw in Node.js URL processing causes an assertion failure in native code when `url.format()` is called with a malformed internationalized domain name (IDN) containing invalid characters, crashing the Node.js process.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Node.js arises from improper handling of malformed internationalized domain names (IDNs) in the url.format() function. When url.format() is called with an IDN containing invalid characters, it triggers an assertion failure in native code, causing the Node.js process to crash. The flaw is classified under CWE-20 (Improper Input Validation) and affects Node.js versions 24.14.0 and 25.8.1. The CVSS 3.0 base score is 5.7, reflecting a medium severity denial of service impact with network attack vector, low attack complexity, requiring privileges and user interaction.
Potential Impact
The vulnerability causes a denial of service by crashing the Node.js process when processing malformed IDNs via url.format(). There is no impact on confidentiality or integrity. No known active exploitation has been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or malformed internationalized domain names with url.format() in affected Node.js versions. Monitor official Node.js channels for updates and patches addressing this issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- hackerone
- Date Reserved
- 2026-01-04T15:00:06.574Z
- Cvss Version
- 3.0
- State
- PUBLISHED
Threat ID: 69ca9c6fe6bfc5ba1d472595
Added to database: 3/30/2026, 3:53:19 PM
Last enriched: 5/11/2026, 1:44:24 AM
Last updated: 5/15/2026, 2:05:17 AM
Views: 105
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