CVE-2023-34104
fast-xml-parser is an open source, pure javascript xml parser. 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 denial of service (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. This problem has been resolved in v4.2.4. Users are advised to upgrade. Users unable to upgrade should avoid using DOCTYPE parsing by setting the `processEntities: false` option.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.13%
- Percentil entre todas las CVEs puntuadas: 65
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-400, CWE-1333
- CWE-1333
Referencias
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/39b0e050bb909e8499478657f84a3076e39ce76c
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/a4bdced80369892ee413bf08e28b78795a2b0d5b
- https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-6w63-h3fj-q4vw
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/39b0e050bb909e8499478657f84a3076e39ce76c
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/a4bdced80369892ee413bf08e28b78795a2b0d5b
- https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-6w63-h3fj-q4vw
JSON original (NVD)
Mostrar
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"id": "CVE-2023-34104",
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}
],
"lastModified": "2026-06-17T06:02:54.207",
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