CVE-2026-25128

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. In versions 5.0.9 through 5.3.3, a RangeError vulnerability exists in the numeric entity processing of fast-xml-parser when parsing XML with out-of-range entity code points (e.g., &#9999999; or &#xFFFFFF;). This causes the parser to throw an uncaught exception, crashing any application that processes untrusted XML input. Version 5.3.4 fixes the issue.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-20",
        "CWE-248"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25128.json"
}

References

Affected packages

Git / github.com/naturalintelligence/fast-xml-parser

Affected ranges

Type

GIT

Repo

https://github.com/naturalintelligence/fast-xml-parser

Events

Introduced

1d3923919e2a9f19a2db2f2918547693286130f3

Fixed

753e770f69d0f30c95b0287f7b8c57e4a93bbc12

Fixed

4e387f61c4a5cef792f6a2f42467013290bf95dc

Database specific

Show details

{
    "extracted_events": [
        {
            "cpe": "cpe:2.3:a:naturalintelligence:fast-xml-parser:*:*:*:*:*:*:*:*",
            "range": [
                {
                    "introduced": "5.0.9"
                },
                {
                    "fixed": "5.3.4"
                }
            ],
            "source": "CPE_RANGE"
        },
        {
            "range": [
                {
                    "fixed": "4e387f61c4a5cef792f6a2f42467013290bf95dc"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "original_tag": "v5.3.4",
            "range": [
                {
                    "fixed": "753e770f69d0f30c95b0287f7b8c57e4a93bbc12"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

v5.*

v5.0.9

v5.1.0

v5.2.0

v5.2.1

v5.2.2

v5.2.3

v5.2.5

v5.3.0

v5.3.1

v5.3.2

v5.3.3

Database specific

source

"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-25128.json"