CVE-2023-23621 json
Discourse vulnerable to ReDoS in user agent parsing
published 2023-01-27 3 y ago modified 2026-09-08 2 mo ago also BIT-discourse-2023-23621 , EUVD-2023-27715 , GHSA-mrfp-54hf-jrcv
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- bitnami discourse 3.0.1
- discourse discourse 3.0.1
- github.com/discourse/discourse@6d92c3c commit
- github.com/discourse/discourse#20002 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 20 mo ago
Exploit prediction
0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | discourse | <3.0.1 |
3.0.1 |
Affected products
- discourse discourse
Classification
- Weakness
-
- CWE-1333 Inefficient Regular Expression Complexity
References
-
github.com
/discourse/discourse/pull/20002
issue-tracking, patch
-
github.com
/discourse/discourse/commit/6d92c3cbdac431db99a450f360a3048bb3aaf458
patch
-
github.com
/discourse/discourse/security/advisories/GHSA-mrfp-54hf-jrcv
third-party-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2023-23621
web
Sources
- CVE List CVE-2023-23621
- NVD CVE-2023-23621
- OSV BIT-discourse-2023-23621
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