Use of Web Browser Cache Containing Sensitive Information in Discourse - CVE-2021-43794
Published: December 1, 2021 / Updated: July 1, 2026
Vulnerability identifier: #VU136610
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2021-43794
CWE-ID: CWE-525
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Civilized Discourse Construction Kit, Inc.
Affected software:
Discourse
Discourse
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a partial denial of service.
The vulnerability exists due to improper cache handling in development-mode header processing when handling requests. A remote attacker can send a specially crafted request to cause a partial denial of service.
Anonymous users may be served a JSON blob instead of the expected HTML page.
How to mitigate CVE-2021-43794
Install security update from vendor's website.