Uncaught Exception Affecting fast-xml-parser package, versions >=5.0.9 <5.3.4
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-FASTXMLPARSER-15155603
- published30 Jan 2026
- disclosed30 Jan 2026
- creditmistersiddd
Introduced: 30 Jan 2026
NewCVE-2026-25128 (opens in a new tab)How to fix?
Upgrade fast-xml-parser to version 5.3.4 or higher.
Overview
fast-xml-parser is a Validate XML, Parse XML, Build XML without C/C++ based libraries
Affected versions of this package are vulnerable to Uncaught Exception in the numeric entity processing when parsing XML containing out-of-range entity code points. An attacker can cause the application to crash by submitting specially crafted XML input that triggers an uncaught exception.