Medium severity · published Oct 7, 2020
CVE-2020-26870
Cure53 DOMPurify before 2.0.17 allows mutation XSS
6.1
CVSS
4.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)4.9% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AE
Application Express · Oracle
before 21.1.0.00.01 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
DO
Dompurify · Cure53
before 2.0.17 · source: NVD
VS
Visual Studio 2017 · Microsoft
15.9 · source: NVD
VS
Visual Studio 2019 · Microsoft
16.0; 16.4; 16.7; 16.8 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26870
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-26870
Patch
https://github.com/cure53/DOMPurify/commit/02724b8eb048dd219d6725b05c3000936f11d62d
Patch
https://github.com/cure53/DOMPurify/compare/2.0.16...2.0.17
Mailing List
https://lists.debian.org/debian-lts-announce/2020/10/msg00029.html
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-26870
Exploit
https://research.securitum.com/mutation-xss-via-mathml-mutation-dompurify-2-0-17-bypass/
Patch
https://www.oracle.com//security-alerts/cpujul2021.html
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7.2
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6.9
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6.8
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