CVE-2023-27266Network attack vector

Team owner email disclosure via teams API

Published Feb 27, 2023 · Updated Dec 6, 2024

Information disclosure in Mattermost 5.12.0 and later, before 7.7.0, allows remote authenticated users to read a team owner's email. The current-user teams API response includes the owner's email without honoring the ShowEmailAddress setting. Team administrator privileges and a configuration intended to hide email addresses are required, and the consequence is limited to that address.

CVSS severity2.7
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

Information disclosure in Mattermost 5.12.0 and later, before 7.7.0, allows remote authenticated users to read a team owner's email. The current-user teams API response includes the owner's email without honoring the ShowEmailAddress setting. Team administrator privileges and a configuration intended to hide email addresses are required, and the consequence is limited to that address.

The record

CVE
CVE-2023-27266
Published
Feb 27, 2023
Updated
Dec 6, 2024
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-200, T1087
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Feb 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 6, 2024Record 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=5.12.0 <7.7.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Mattermost · Mattermostversion=5.12.0 <7.7.0

Published CVSS scores

2.7Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1087Account Discovery

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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