CVE-2024-40643: joplin XSS — Exploit & Fix

Description

Joplin is a free, open source note taking and to-do application. Joplin fails to take into account that "<" followed by a non letter character will not be considered html. As such it is possible to do an XSS by putting an "illegal" tag within a tag.

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CVSS v3.1 Score

9.6

CRITICAL

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

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
joplin_project	joplin	< 3.0.15

References

Advisories & Patches

https://github.com/laurent22/joplin/commit/b220413a9b5ed55fb1f565ac786a5c231da8bc87 https://github.com/laurent22/joplin/security/advisories/GHSA-g796-3g6g-jmmc

Exploits

https://github.com/laurent22/joplin/security/advisories/GHSA-g796-3g6g-jmmc

Frequently Asked Questions

What is CVE-2024-40643? +

Joplin is a free, open source note taking and to-do application. Joplin fails to take into account that "<" followed by a non letter character will not be considered html. As such it is possible to do an XSS by putting an "illegal" tag within a tag. It has a CVSS v3.1 base score of 9.6 (CRITICAL).

How severe is CVE-2024-40643? +

CVE-2024-40643 has a CVSS v3.1 score of 9.6 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2024-40643? +

CVE-2024-40643 affects products from joplin_project, specifically: joplin. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-40643? +

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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CVE-2024-40643