CVE-2022-23549Network attack vector

Service interruption via HTML-comment length bypass

Published Jan 5, 2023 · Updated Mar 10, 2025

Improper input validation in Discourse stable before 2.8.14 and beta before 2.9.0.beta16 allows remote authenticated users to submit overlength posts. StrippedLengthValidator measured a sanitized value that removed HTML comments instead of checking the raw post body against max_post_length. Posting privileges are required, and accepted oversized content can interrupt service without disclosing protected data.

CVSS severity5.7
Medium
EPSS probability0.57%
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 stable before 2.8.14 and beta before 2.9.0.beta16 allows remote authenticated users to submit overlength posts. StrippedLengthValidator measured a sanitized value that removed HTML comments instead of checking the raw post body against max_post_length. Posting privileges are required, and accepted oversized content can interrupt service without disclosing protected data.

The record

CVE
CVE-2022-23549
Published
Jan 5, 2023
Updated
Mar 10, 2025
Vendor
Discourse
Product
Discourse
Classifications
CWE-20, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 5, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=2.8.14 <2.8.14
  2. Affected versionversion=2.9.0.beta0 <=2.9.0.beta0
  3. Affected versionversion=2.9.0.beta16 <2.9.0.beta16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=2.8.14 <2.8.14; version=2.9.0.beta0 <=2.9.0.beta0; version=2.9.0.beta16 <2.9.0.beta16

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.7GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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