Vulnerability Database · npm · fast-xml-parser · Version
fast-xml-parser 4.2.3
4.2.3 is affected by 7 vulnerabilities.
The vulnerabilities that cover this exact version are listed below with the fixed version to move to. The upgrade Vulert recommends: 5.11.2.
Critical 1 High 3 Medium 2 Low 1 Unrated 0
-
Released 05 Jun 2023
Licence MIT
Also known from other sources 7
Newer releases 201
Database updated 23/Oct/2026
Release and licence data published by the npm registry. Licence information is not legal advice.
Concerned about your application's security?
Vulert continues monitoring your dependencies and alerts you when new vulnerabilities are disclosed. No installation and no source-code access required.
01 Vulnerabilities affecting this version
fast-xml-parser 4.2.3 vulnerabilities
7 vulnerabilities cover fast-xml-parser 4.2.3. Open the full list in the database.
| Vulnerability | Severity | Fixed version | Disclosed |
|---|---|---|---|
| CVE-2026-25896: fast-xml-parser Entity Encoding Bypass via Regex Injection | 9.3 critical | 5.3.5 | 20 Feb 2026 |
| CVE-2026-33036: fast-xml-parser Numeric Entity Expansion Bypass Vulnerability | 7.5 high | 5.5.6 | 17 Mar 2026 |
| CVE-2026-26278: fast-xml-parser Denial of Service via Unrestricted Entity Expansion | 7.5 high | 5.3.6 | 17 Feb 2026 |
| CVE-2023-34104: fast-xml-parser Regex Injection via Doctype Entities | 7.5 high | 4.2.4 | 06 Jun 2023 |
| CVE-2026-41650: fast-xml-parser XMLBuilder Comment and CDATA Injection Vulnerability | 6.1 medium | 5.7.0 | 22 Apr 2026 |
| CVE-2026-33349: fast-xml-parser Entity Expansion Limits Bypass Vulnerability | 5.9 medium | 5.5.7 | 19 Mar 2026 |
| CVE-2026-27942: fast-xml-parser Stack Overflow Vulnerability with preserveOrder | 2.7 low | 5.3.8 | 26 Feb 2026 |
Looking for another version, or everything Vulert holds for fast-xml-parser?
Questions
About fast-xml-parser 4.2.3
Is fast-xml-parser 4.2.3 vulnerable?
Yes. 7 vulnerabilities in the Vulert database cover fast-xml-parser 4.2.3: 1 critical, 3 high, 2 medium and 1 low. The upgrade Vulert recommends is 5.11.2, and each entry above names the fixed version to move to.
Which version of fast-xml-parser should I use instead of 4.2.3?
5.11.2 is the version Vulert recommends for this release line. The version table on the package page lists every release with the vulnerabilities recorded against it.
Is 4.2.3 the latest release of fast-xml-parser?
No. 4.2.3 was published 05 Jun 2023, and newer releases exist. Newer is not automatically safer — the version table on the package page shows what each release carries.
How do I monitor fast-xml-parser for upcoming vulnerabilities?
Upload the manifest or SBOM for your application at vulert.com/scanner and Vulert keeps checking the fast-xml-parser version you actually run against new disclosures, then alerts you when one affects it. There is no installation and no source-code access required.