CVE-2026-25896
critical · 9.3fast-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 during entity replacement, allowing an attacker to shadow built-in XML entities (<, >, &, ", ') with arbitrary values. This bypasses entity encoding and leads to XSS when parsed output is rendered. This vulnerability is fixed in 5.3.5.
9.3
CVSS
0.5%
EPSS (exploit prob.)
40th
EPSS percentile
2026-02-20
Published
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
Weaknesses
CWE-185CWE-79
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| naturalintelligence | fast-xml-parser | >= 4.1.3, < 5.3.5 |
Check a specific version with /api/v1/cve/match.
References
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/943ef0eb1b2d3284e72dd74f44a042ee9f07026e
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/ddcd0acf26ddd682cb0dc15a2bd6aa3b96bb1e69
- https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.3.5
- https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-m7jm-9gc2-mpf2
- https://access.redhat.com/errata/RHSA-2026:40984
- https://access.redhat.com/errata/RHSA-2026:41941
- https://access.redhat.com/errata/RHSA-2026:41944
- https://access.redhat.com/errata/RHSA-2026:51349
- https://access.redhat.com/errata/RHSA-2026:6174
- https://access.redhat.com/errata/RHSA-2026:6802
- https://access.redhat.com/errata/RHSA-2026:7110
- https://access.redhat.com/errata/RHSA-2026:7128
- https://access.redhat.com/security/cve/CVE-2026-25896
- https://bugzilla.redhat.com/show_bug.cgi?id=2441501
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-25896.json
Query this programmatically:
curl https://evil-db.io/api/v1/cve/CVE-2026-25896