CVE-2021-21366

Misinterpretation of malicious XML input

Description

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. xmldom versions 0.4.0 and older do not correctly preserve system identifiers, FPIs or namespaces when repeatedly parsing and serializing maliciously crafted documents. This may lead to unexpected syntactic changes during XML processing in some downstream applications. This is fixed in version 0.5.0. As a workaround downstream applications can validate the input and reject the maliciously crafted documents.

Categories

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.75% Top 30%
Vendor Advisory github.com
Affected: xmldom xmldom
Published at:
Updated at:

References

Link Tags
https://github.com/xmldom/xmldom/security/advisories/GHSA-h6q6-9hqw-rwfv vendor advisory
https://www.npmjs.com/package/xmldom product
https://github.com/xmldom/xmldom/releases/tag/0.5.0 release notes
https://github.com/xmldom/xmldom/commit/d4201b9dfbf760049f457f9f08a3888d48835135 patch
https://lists.debian.org/debian-lts-announce/2023/01/msg00000.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-21366?
CVE-2021-21366 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21366?
To fix CVE-2021-21366, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21366 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21366 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21366?
CVE-2021-21366 affects xmldom xmldom.
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