CVE-2023-43659

Name: CVE-2023-43659
Creator: NVD / NIST
Published: 2023-10-16T22:15:12.237+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.42%

Last modified Jun 17, 2026

CVE-2023-43659 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. Discourse is an open source platform for community discussion. Improper escaping of user input allowed for Cross-site Scripting attacks via the digest email preview UI. EPSS estimates a 0.42% chance of exploitation in the next 30 days.

Description

Discourse is an open source platform for community discussion. Improper escaping of user input allowed for Cross-site Scripting attacks via the digest email preview UI. This issue only affects sites with CSP disabled. This issue has been patched in the 3.1.1 stable release as well as the 3.2.0.beta1 release. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum.

Metrics

CVSS 3.1

5.4/10

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

EPSS Probability

0.42%

33.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions	Update
Discourse	Discourse	<= 3.1.1	—
Discourse	Discourse	3.2.0	Beta1

References

https://developer.mozilla.org/en-US/docs/Web/HTTP/CSPThird Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-g4qg-5q2h-m8phVendor Advisory
https://developer.mozilla.org/en-US/docs/Web/HTTP/CSPThird Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-g4qg-5q2h-m8phVendor Advisory

Timeline

Published: Oct 16, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-43659?

How severe is CVE-2023-43659?

CVE-2023-43659 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.42% probability of exploitation in the next 30 days.

How do I fix CVE-2023-43659?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-43659?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST