CVE-2023-6551: class.upload.php File Upload RCE (CVSS 5.4)

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.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-434 Unrestricted Upload

Affected Products

Vendor	Product	Versions
verot	class.upload.php	All

References

Other References

https://cert.pl/en/posts/2024/01/CVE-2023-6551 https://cert.pl/posts/2024/01/CVE-2023-6551 https://cert.pl/en/posts/2024/01/CVE-2023-6551 https://cert.pl/posts/2024/01/CVE-2023-6551

Frequently Asked Questions

What is CVE-2023-6551? +

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. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2023-6551? +

CVE-2023-6551 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-6551? +

CVE-2023-6551 affects products from verot, specifically: class.upload.php. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6551? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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