CVE-2021-3313

Public Exploit

Description

Plone CMS until version 5.2.4 has a stored Cross-Site Scripting (XSS) vulnerability in the user fullname property and the file upload functionality. The user's input data is not properly encoded when being echoed back to the user. This data can be interpreted as executable code by the browser and allows an attacker to execute JavaScript in the context of the victim's browser if the victim opens a vulnerable page containing an XSS payload.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory plone.org Vendor Advisory plone.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://plone.org/download/releases/5.2.3 release notes vendor advisory
https://www.compass-security.com/fileadmin/Research/Advisories/2021-07_CSNC-2021-013_XSS_in_Plone_CMS.txt third party advisory exploit
https://plone.org/security/hotfix/20210518 vendor advisory
http://www.openwall.com/lists/oss-security/2021/05/22/1 third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-3313?
CVE-2021-3313 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3313?
To fix CVE-2021-3313, 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-2021-3313 being actively exploited in the wild?
It is possible that CVE-2021-3313 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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