XSS in Naturalintelligence Fast-xml-parser
CVE-2026-25896
fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. From 4.1.3to before 5.3.5, a dot (.) in a DOCTYPE entity name is treated as a regex wildcard d…
EPSS: 0.004 (36.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N.
Affected products
- Naturalintelligence Fast-xml-parser — versions >= 5.0.0, < 5.3.5, >= 4.1.3, < 4.5.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-25896?
- CVE-2026-25896 is a critical-severity vulnerability in Naturalintelligence Fast-xml-parser, classified under Incorrect Regular Expression. CVSS score: 9.3/10. Published 2026-02-20.
- How severe is CVE-2026-25896?
- Critical severity. CVSS v3 base score is 9.3 out of 10.