CVE-2023-43659 Cross-site Scripting via email preview when CSP disabled in Discourse
Attackers can execute arbitrary scripts via email preview in Discourse when Content Security Policy is disabled, potentially compromising user accounts.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2023-43659?
CVE-2023-43659 is a high-severity cross-site scripting vulnerability in Discourse Discourse, published on 16 Oct 2023. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2023-43659?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | All versions to 3.1.1 | None |
Products include Discourse Discourse.
How do I fix CVE-2023-43659?
No fix has been published for CVE-2023-43659 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2023-43659 being exploited?
There is no known exploitation of CVE-2023-43659 in the wild and no public exploit code.
Other vulnerabilities in Discourse Discourse
- CVE-2021-41163 RCE via malicious SNS subscription payload
- CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file
- CVE-2022-39356 Discourse user account takeover via email and invite link
- CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes
- CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint
Sources
Also known as BIT-discourse-2023-43659, GHSA-g4qg-5q2h-m8ph.