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TI-2022-20262 Aliases CVE-2022-41921

Discourse chat messages should have a maximum character limit

Priority LOW 21CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.

Summary

Discourse is an open-source discussion platform. Prior to version 2.9.0.beta13, users can post chat messages of an unlimited length, which can cause a denial of service for other users when posting huge amounts of text. Users should upgrade to version 2.9.0.beta13, where a limit has been introduced. No known workarounds are available.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0057 47th percentileScored 2026-11-07
Fix Fixed discourse (discourse): 2.9.0.beta13

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
discoursediscoursebefore 2.9.0.beta132.9.0.beta13Patch availableCNA
  • discourse Vendordiscourse Affected before 2.9.0.beta13 Fixed in 2.9.0.beta13 Patch available CNA

CPE configurations NVD · 13

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*before 2.9.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta1:*:*:*:*:*:*2.9.0 beta1Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta10:*:*:*:*:*:*2.9.0 beta10Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta11:*:*:*:*:*:*2.9.0 beta11Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta12:*:*:*:*:*:*2.9.0 beta12Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta2:*:*:*:*:*:*2.9.0 beta2Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta3:*:*:*:*:*:*2.9.0 beta3Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta4:*:*:*:*:*:*2.9.0 beta4Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta5:*:*:*:*:*:*2.9.0 beta5Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta6:*:*:*:*:*:*2.9.0 beta6Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* Versions before 2.9.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta1:*:*:*:*:*:* Versions 2.9.0 beta1 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta10:*:*:*:*:*:* Versions 2.9.0 beta10 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta11:*:*:*:*:*:* Versions 2.9.0 beta11 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta12:*:*:*:*:*:* Versions 2.9.0 beta12 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta2:*:*:*:*:*:* Versions 2.9.0 beta2 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta3:*:*:*:*:*:* Versions 2.9.0 beta3 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta4:*:*:*:*:*:* Versions 2.9.0 beta4 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta5:*:*:*:*:*:* Versions 2.9.0 beta5 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta6:*:*:*:*:*:* Versions 2.9.0 beta6 Vulnerable ·discourse
Show 3 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:2.9.0:beta7:*:*:*:*:*:*2.9.0 beta7Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta8:*:*:*:*:*:*2.9.0 beta8Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2.9.0:beta9:*:*:*:*:*:*2.9.0 beta9Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta7:*:*:*:*:*:* Versions 2.9.0 beta7 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta8:*:*:*:*:*:* Versions 2.9.0 beta8 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2.9.0:beta9:*:*:*:*:*:* Versions 2.9.0 beta9 Vulnerable ·discourse

Remediation

  • Fix · CNA discourse (discourse) Fixed in 2.9.0.beta13

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-41921

References

Patch 1

Advisory 1

  • TI-2021-19656 Denial of Service in discourse CVSS 3.1MEDIUM 6.8
  • TI-2024-36150 Potential Backup file leaked via Nginx in Discourse CVSS 3.1HIGH 7.5
  • TI-2021-18002 RCE via malicious SNS subscription payload CVSS 3.1CRITICAL 10.0
  • TI-2026-24651 Discourse: Open redirect via `sso_destination_url` cookie in `enter` CVSS 4.0MEDIUM 5.1
  • TI-2026-22278 Discourse leaks private topic title and post excerpt via user action API endpoint CVSS 4.0HIGH 8.7
  • TI-2023-24152 Unauthenticated access to new private chat messages in Discourse CVSS 3.1HIGH 7.5
See all 262 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences