High severity · published Jan 28, 2023
CVE-2023-23621
Discourse is an open-source discussion platform
7.5
CVSS
0.9%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
Discourse · Discourse
before 3.0.1; 1.1.0; 1.1.0; 1.1.0; 1.1.0; 1.1.0; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-23621
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-23621
Patch
https://github.com/discourse/discourse/commit/6d92c3cbdac431db99a450f360a3048bb3aaf458
Issue Tracking
https://github.com/discourse/discourse/pull/20002
Third Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-mrfp-54hf-jrcv
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