Answer in brief
CVE-2026-25896 records a Critical severity (CVSS 9.3) vulnerability in fast-xml-parser has an entity encoding bypass via regex injection in DOCTYPE entity names. The current sources do not mark it as known exploited. The current feed maps NaturalIntelligence/fast-xml-parser (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-25896 records a Critical severity (CVSS 9.3) vulnerability in fast-xml-parser has an entity encoding bypass via regex injection in DOCTYPE entity names. The current sources do not mark it as known exploited. The current feed maps NaturalIntelligence/fast-xml-parser (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps NaturalIntelligence/fast-xml-parser (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| NaturalIntelligence/fast-xml-parsergeneric | >= 5.0.0, < 5.3.5 || >= 4.1.3, < 4.5.4 | Not reported |
Published upstream
Feb 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
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 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.
Quoted source text, attributed separately from HOL analysis.
CVSS is 9.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps NaturalIntelligence/fast-xml-parser (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| NaturalIntelligence/fast-xml-parsergeneric | >= 5.0.0, < 5.3.5 || >= 4.1.3, < 4.5.4 | Not reported |
Published upstream
Feb 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
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 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.
Quoted source text, attributed separately from HOL analysis.