Medium severity · published Dec 18, 2025
CVE-2020-36891
Kentico Xperience <= 12.0.49 File Upload Stored XSS
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
A stored cross-site scripting vulnerability in Kentico Xperience allows attackers to upload files with spoofed Content-Type that do not match file extensions. Attackers can exploit this vulnerability by uploading malicious files with manipulated MIME types, allowing malicious scripts to execute in users' browsers.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
XP
Xperience · Kentico
through 12.0.49 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36891
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-36891
Product
https://devnet.kentico.com/download/hotfixes
Third Party Advisory
https://www.vulncheck.com/advisories/kentico-xperience-file-upload-stored-xss
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