CVE-2022-41921Network attack vector

Service interruption via unbounded chat message length

Published Nov 28, 2022 · Updated Apr 23, 2025

Improper input validation in Discourse before 2.9.0.beta13 allows remote authenticated users to interrupt service with oversized chat messages. The Chat::ChatMessage model accepts message content without maximum-length validation, allowing extremely large bodies to be stored and rendered. A forum account and a victim who loads the resulting chat content are required, and the reported consequence is denial of service for other users.

CVSS severity3.5
Low
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Discourse before 2.9.0.beta13 allows remote authenticated users to interrupt service with oversized chat messages. The Chat::ChatMessage model accepts message content without maximum-length validation, allowing extremely large bodies to be stored and rendered. A forum account and a victim who loads the resulting chat content are required, and the reported consequence is denial of service for other users.

The record

CVE
CVE-2022-41921
Published
Nov 28, 2022
Updated
Apr 23, 2025
Vendor
Discourse
Product
Discourse
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 28, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.9.0.beta13

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=< 2.9.0.beta13

Published CVSS scores

4.3NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
3.5GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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