CVE-2026-4990Public exploitNetwork attack vector

Unauthorized account creation via client-controlled signup flag

Published Mar 27, 2026 · Updated Mar 27, 2026

Improper authorization in Chatwoot 4.11.0 through 4.11.1 allows remote attackers to create accounts when signup is disabled. The /app/login response exposes signupEnabled as a client-side gate, while the signup API fails to enforce the disabled setting server-side and accepts a modified true value. No authentication is required; successful exploitation creates an unauthorized account, reported as administrative, on an instance intended to block registration.

CVSS severity7.3
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Chatwoot 4.11.0 through 4.11.1 allows remote attackers to create accounts when signup is disabled. The /app/login response exposes signupEnabled as a client-side gate, while the signup API fails to enforce the disabled setting server-side and accepts a modified true value. No authentication is required; successful exploitation creates an unauthorized account, reported as administrative, on an instance intended to block registration.

The record

CVE
CVE-2026-4990
Published
Mar 27, 2026
Updated
Mar 27, 2026
Vendor
Chatwoot
Product
Chatwoot
Classifications
CWE-285, CWE-266, T1136
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 27, 2026Record 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=4.11.0
  2. Affected versionversion=4.11.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Chatwoot · Chatwootversion=4.11.0; version=4.11.1

Published CVSS scores

5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
7.5VulDBAV:N/AC:L/Au:N/C:P/I:P/A:P
7.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-285Improper Authorization
CWE-266Incorrect Privilege Assignment
T1136Create Account

Public exploit references

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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