CVE-2023-6551

Stored XSS in class.upload.php

Description

As a simple library, class.upload.php does not perform an in-depth check on uploaded files, allowing a stored XSS vulnerability when the default configuration is used. Developers must be aware of that fact and use extension whitelisting accompanied by forcing the server to always provide content-type based on the file extension. The README has been updated to include these guidelines.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.06%
Third-Party Advisory cert.pl Third-Party Advisory cert.pl
Affected: class.upload.php class.upload.php
Published at:
Updated at:

References

Link Tags
https://cert.pl/posts/2024/01/CVE-2023-6551 third party advisory
https://cert.pl/en/posts/2024/01/CVE-2023-6551 third party advisory

Frequently Asked Questions

What is the severity of CVE-2023-6551?
CVE-2023-6551 has been scored as a medium severity vulnerability.
How to fix CVE-2023-6551?
To fix CVE-2023-6551, 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-2023-6551 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6551 is being actively exploited. 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-2023-6551?
CVE-2023-6551 affects class.upload.php class.upload.php.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.