Use of Web Browser Cache Containing Sensitive Information in Discourse - CVE-2021-41271
Published: November 15, 2021 / Updated: July 1, 2026
Vulnerability identifier: #VU136562
CSH Severity: Low
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-41271
CWE-ID: CWE-525
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper cache control in intermediate proxy caching behavior when handling a maliciously formed request. A remote attacker can send a specially crafted request to cause a denial of service.
The issue can cause an error response to be cached by intermediate proxies.
Affected software
Discourse
How to mitigate CVE-2021-41271
Install security update from vendor's website.
Discourse - addressed in versions 2.7.10, 2.8.0 beta8