CVE-2020-26870

Public Exploit

Description

Cure53 DOMPurify before 2.0.17 allows mutation XSS. This occurs because a serialize-parse roundtrip does not necessarily return the original DOM tree, and a namespace can change from HTML to MathML, as demonstrated by nesting of FORM elements.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
Vendor Advisory microsoft.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://research.securitum.com/mutation-xss-via-mathml-mutation-dompurify-2-0-17-bypass/ third party advisory exploit
https://github.com/cure53/DOMPurify/commit/02724b8eb048dd219d6725b05c3000936f11d62d third party advisory patch
https://github.com/cure53/DOMPurify/compare/2.0.16...2.0.17 third party advisory patch
https://lists.debian.org/debian-lts-announce/2020/10/msg00029.html third party advisory mailing list
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-26870 patch vendor advisory
https://www.oracle.com//security-alerts/cpujul2021.html third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2020-26870?
CVE-2020-26870 has been scored as a medium severity vulnerability.
How to fix CVE-2020-26870?
To fix CVE-2020-26870, 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-2020-26870 being actively exploited in the wild?
It is possible that CVE-2020-26870 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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