CVE-2024-35234: discourse XSS — Fix

Description

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch, an attacker can execute arbitrary JavaScript on users’ browsers by posting a specific URL containing maliciously crafted meta tags. This issue only affects sites with Content Security Polic (CSP) disabled. The problem has been patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch. As a workaround, ensure CSP is enabled on the forum.

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CVSS v3.1 Score

4.2

MEDIUM

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

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
discourse	discourse	< 3.2.3
discourse	discourse	< 3.3.0
discourse	discourse	All
discourse	discourse	All

References

Advisories & Patches

https://github.com/discourse/discourse/commit/26aef0c288839378b9de5819e96eac8cf4ea60fd https://github.com/discourse/discourse/commit/311b737c910cf0a69f61e1b8bc0b78374b6619d2 https://github.com/discourse/discourse/commit/26aef0c288839378b9de5819e96eac8cf4ea60fd https://github.com/discourse/discourse/commit/311b737c910cf0a69f61e1b8bc0b78374b6619d2

Other References

https://github.com/discourse/discourse/security/advisories/GHSA-5chg-hm8c-wc58 https://github.com/discourse/discourse/security/advisories/GHSA-5chg-hm8c-wc58

Frequently Asked Questions

What is CVE-2024-35234? +

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch, an attacker can execute arbitrary JavaScript on users’ browsers by posting a specific URL containing maliciously crafted meta tags. This issue only affects sites with Content Security Polic (CSP) disabled. The problem has been patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch. As a workaround, ensure CSP is enabled on the forum. It has a CVSS v3.1 base score of 4.2 (MEDIUM).

How severe is CVE-2024-35234? +

CVE-2024-35234 has a CVSS v3.1 score of 4.2 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-2024-35234? +

CVE-2024-35234 affects products from discourse, specifically: discourse. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-35234? +

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-2024-35234