CVE-2021-43991

Public Exploit
Persistent XSS via Avatar Upload in Kentico Xperience CMS

Description

The Kentico Xperience CMS version 13.0 – 13.0.43 is vulnerable to a persistent Cross-Site Scripting (XSS) vulnerability (also known as Stored or Second-Order XSS). Persistent XSS vulnerabilities occur when the application stores and retrieves client supplied data without proper handling of dangerous content. This type of XSS vulnerability is exploited by submitting malicious script content to the application which is then retrieved and executed by other application users. The attacker could exploit this to conduct a range of attacks against users of the affected application such as session hijacking, account take over and accessing sensitive data.

Category

6.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory appcheck-ng.com
Affected: Kentico Kentico Xperience XMS
Published at:
Updated at:

References

Link Tags
https://appcheck-ng.com/persistent-xss-kentico-cms/ exploit third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-43991?
CVE-2021-43991 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43991?
To fix CVE-2021-43991, 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-2021-43991 being actively exploited in the wild?
It is possible that CVE-2021-43991 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.
What software or system is affected by CVE-2021-43991?
CVE-2021-43991 affects Kentico Kentico Xperience XMS.
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