CVSS 7.5 · High EPSS 0,73%
Kerentanan Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') pada naturalintelligence fast-xml-parser. Skor CVSS 3.1 7.5 (High) menurut github.com.
fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. Versions 4.0.0-beta.3 through 5.5.5 contain a bypass vulnerability where numeric character references (&#NNN;, &#xHH;) and standard XML entities completely evade the entity expansion limits (e.g., maxTotalExpansions, maxExpandedLength) added to fix CVE-2026-26278, enabling XML entity expansion Denial of Service. The root cause is that replaceEntitiesValue() in OrderedObjParser.js only enforces expansion counting on DOCTYPE-defined entities while the lastEntities loop handling numeric/standard entities performs no counting at all. An attacker supplying 1M numeric entity references like A can force ~147MB of memory allocation and heavy CPU usage, potentially crashing the process—even when developers have configured strict limits. This issue has been fixed in version 5.5.6.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| naturalintelligence | fast-xml-parser | Versi 4.0.1 hingga sebelum 5.5.6 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta3 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta4 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta5 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta6 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta7 |
| naturalintelligence | fast-xml-parser | Versi 4.0.0 beta8 |