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  5. CVE-2023-26920

CVE-2023-26920: fast-xml-parser vulnerable to Prototype Pollution through tag or attribute name

June 13, 2023

Impact

As a part of this vulnerability, user was able to se code using __proto__ as a tag or attribute name.

const { XMLParser, XMLBuilder, XMLValidator} = require("fast-xml-parser");

let XMLdata = "<__proto__><polluted>hacked</polluted></__proto__>"

const parser = new XMLParser();
let jObj = parser.parse(XMLdata);

console.log(jObj.polluted) // should return hacked

Patches

The problem has been patched in v4.1.2

Workarounds

User can check for “proto” in the XML string before parsing it to the parser.

References

https://gist.github.com/Sudistark/a5a45bd0804d522a1392cb5023aa7ef7

References

  • gist.github.com/Sudistark/a5a45bd0804d522a1392cb5023aa7ef7
  • github.com/NaturalIntelligence/fast-xml-parser/commit/2b032a4f799c63d83991e4f992f1c68e4dd05804
  • github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-x3cc-x39p-42qx
  • github.com/advisories/GHSA-x3cc-x39p-42qx

Code Behaviors & Features

Detect and mitigate CVE-2023-26920 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →

Affected versions

All versions before 4.1.2

Fixed versions

  • 4.1.2

Solution

Upgrade to version 4.1.2 or above.

Source file

npm/fast-xml-parser/CVE-2023-26920.yml

Spotted a mistake? Edit the file on GitLab.

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