GitHub Advisoryadvisory · npm

GHSA-6w63-h3fj-q4vw fast-xml-parser vulnerable to Regex Injection via Doctype Entities

HIGH Published 2023-06-06 Modified 2026-03-09 Official page ↗
Aliases
CVE-2023-34104
Ecosystem
npm
Packages
fast-xml-parser
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-1333, CWE-400
Reviewed
2023-06-06

Affected packages

• npm fast-xml-parser: >= 4.1.3, < 4.2.4 → fixed in 4.2.4

Description

Impact "fast-xml-parser" allows special characters in entity names, which are not escaped or sanitized. Since the entity name is used for creating a regex for searching and replacing entities in the XML body, an attacker can abuse it for DoS attacks. By crafting an entity name that results in an intentionally bad performing regex and utilizing it in the entity replacement step of the parser, this can cause the parser to stall for an indefinite amount of time. Patches The problem has been resolved in v4.2.4 Workarounds Avoid using DOCTYPE parsing by `processEntities: false` option.

Related

Alias · CVE (1)

  • CVE-2023-34104 fast-xml-parser is an open source, pure javascript xml parser. vulnerability

Weakness · CWE (2)

  • CWE-1333 Inefficient Regular Expression Complexity weakness
  • CWE-400 Uncontrolled Resource Consumption weakness

References