{"cve":"CVE-2023-23621","nvd":{"published":"2023-01-28T00:15:09.373","modified":"2026-06-17T05:37:36.250","status":"Modified","description":"Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches, a malicious user can cause a regular expression denial of service using a carefully crafted user agent. This issue is patched in version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches. There are no known workarounds.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-1333"],"references":["https://github.com/discourse/discourse/commit/6d92c3cbdac431db99a450f360a3048bb3aaf458","https://github.com/discourse/discourse/pull/20002","https://github.com/discourse/discourse/security/advisories/GHSA-mrfp-54hf-jrcv","https://github.com/discourse/discourse/commit/6d92c3cbdac431db99a450f360a3048bb3aaf458","https://github.com/discourse/discourse/pull/20002"],"products":["discourse:discourse"],"source":"nvd","synced_at":"2026-10-19T21:37:38.595364862+00:00"},"epss":{"cve":"CVE-2023-23621","score":0.00868,"percentile":0.58763,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}