Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a malicious user can edit a post in a topic and cause a DoS with a carefully crafted edit reason. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability.
https://github.com/discourse/discourse/security/advisories/GHSA-pjv6-47x6-mx7c
https://github.com/discourse/discourse/commit/dcc825bda505a344eda403a1b8733f30e784034a