CVE-2022-23548Network attack vector

Authenticated service interruption via inefficient post-parsing regex

Published Jan 5, 2023 · Updated Mar 10, 2025

ReDoS in Discourse before 2.8.14 and 2.9.0.beta0 through 2.9.0.beta15 allows remote authenticated users to interrupt the forum. The post parser used regex gsub to remove trailing whitespace, causing crafted post text to consume excessive processing time through inefficient matching. A low-privileged network account and a crafted post are required; successful exploitation blocks post processing and degrades service availability.

CVSS severity6.5
Medium
EPSS probability0.73%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

ReDoS in Discourse before 2.8.14 and 2.9.0.beta0 through 2.9.0.beta15 allows remote authenticated users to interrupt the forum. The post parser used regex gsub to remove trailing whitespace, causing crafted post text to consume excessive processing time through inefficient matching. A low-privileged network account and a crafted post are required; successful exploitation blocks post processing and degrades service availability.

The record

CVE
CVE-2022-23548
Published
Jan 5, 2023
Updated
Mar 10, 2025
Vendor
Discourse
Product
Discourse
Classifications
CWE-1333, T1499.004
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

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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=< 2.8.14
  2. Affected versionversion=>= 2.9.0.beta0, < 2.9.0.beta16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

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

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
T1499.004Application or System Exploitation

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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