CVE-2024-4023: flatpress XSS — Exploit & Fix

Description

A stored cross-site scripting (XSS) vulnerability exists in flatpressblog/flatpress version 1.3. When a user uploads a file with a `.xsig` extension and directly accesses this file, the server responds with a Content-type of application/octet-stream, leading to the file being processed as an HTML file. This allows an attacker to execute arbitrary JavaScript code, which can be used to steal user cookies, perform HTTP requests, and access content of the same origin.

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CVSS v3.1 Score

8.1

HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
flatpress	flatpress	All

References

Advisories & Patches

https://github.com/flatpressblog/flatpress/commit/3c9cc69364a45fd3f92d4bd606344b5dd1205d6a

Exploits

https://huntr.com/bounties/ed803c13-0858-4c22-93ba-bf2384ab1e9d

Frequently Asked Questions

What is CVE-2024-4023? +

A stored cross-site scripting (XSS) vulnerability exists in flatpressblog/flatpress version 1.3. When a user uploads a file with a `.xsig` extension and directly accesses this file, the server responds with a Content-type of application/octet-stream, leading to the file being processed as an HTML file. This allows an attacker to execute arbitrary JavaScript code, which can be used to steal user cookies, perform HTTP requests, and access content of the same origin. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2024-4023? +

CVE-2024-4023 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-4023? +

CVE-2024-4023 affects products from flatpress, specifically: flatpress. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-4023? +

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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