Discourse up to 3.0.0/3.1.0.beta1 redos

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as problematic, was found in Discourse up to 3.0.0/3.1.0.beta1. Affected is an unknown part. The manipulation with an unknown input leads to a redos vulnerability. CWE is classifying the issue as CWE-1333. The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. This is going to have an impact on availability. CVE summarizes:

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.

The weakness was shared 01/28/2023 as GHSA-mrfp-54hf-jrcv. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2023-23621 since 01/16/2023. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1449.003.

Upgrading to version 3.0.1 or 3.1.0.beta2 eliminates this vulnerability. Applying the patch 6d92c3cbdac431db99a450f360a3048bb3aaf458 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.




  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 8.6
CNA Vector (GitHub, Inc.): 🔒



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Redos
CWE: CWE-1333 / CWE-400 / CWE-404
ATT&CK: T1449.003

Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Discourse 3.0.1/3.1.0.beta2
Patch: 6d92c3cbdac431db99a450f360a3048bb3aaf458


01/16/2023 CVE reserved
01/28/2023 +12 days Advisory disclosed
01/28/2023 +0 days VulDB entry created
02/23/2023 +26 days VulDB last update


Advisory: GHSA-mrfp-54hf-jrcv
Status: Confirmed

CVE: CVE-2023-23621 (🔒)


Created: 01/28/2023 01:31 PM
Updated: 02/23/2023 07:10 PM
Changes: 01/28/2023 01:31 PM (50), 02/23/2023 07:10 PM (11)
Complete: 🔍


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