CVE-2026-4926

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-4926
Impact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.

7.5 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://cna.openjsf.org/security-advisories.html Third Party Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:pillarjs:path-to-regexp:*:*:*:*:*:node.js:*:*
History

16 Apr 2026, 18:04

Type Values Removed Values Added
First Time Pillarjs
Pillarjs path-to-regexp
CPE cpe:2.3:a:pillarjs:path-to-regexp:*:*:*:*:*:node.js:*:*
References () https://cna.openjsf.org/security-advisories.html - () https://cna.openjsf.org/security-advisories.html - Third Party Advisory

30 Mar 2026, 13:26

Type Values Removed Values Added
Summary
  • (es) Impacto: Se genera una expresión regular defectuosa siempre que se tienen múltiples grupos opcionales secuenciales (sintaxis de llaves), como `{a}{b}{c}:z`. La expresión regular generada crece exponencialmente con el número de grupos, causando denegación de servicio. Parches: Corregido en la versión 8.4.0. Soluciones alternativas: Limitar el número de grupos opcionales secuenciales en los patrones de ruta. Evitar pasar entradas controladas por el usuario como patrones de ruta.

26 Mar 2026, 19:17

Type Values Removed Values Added
New CVE
Information

Published : 2026-03-26 19:17

Updated : 2026-04-16 18:04

NVD link : CVE-2026-4926

Mitre link : CVE-2026-4926

CVE.ORG link : CVE-2026-4926

JSON object : View

Products Affected

pillarjs

  • path-to-regexp
CWE
CWE-400

Uncontrolled Resource Consumption

CWE-1333

Inefficient Regular Expression Complexity