CVE-2023-47858Network attack vector

Cross-team channel disclosure via missing permission check

Published Jan 2, 2024 · Updated Jun 17, 2025

Improper access control in Mattermost allows remote authenticated users to read archived public-channel details belonging to other teams. The GET /api/v4/teams//channels/deleted handler fails to enforce the target team's manage_team permission before returning deleted-channel metadata. Membership in one team is sufficient to query another team's identifier; the reported exposure is limited to archived public-channel details.

CVSS severity4.3
Medium
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Mattermost allows remote authenticated users to read archived public-channel details belonging to other teams. The GET /api/v4/teams//channels/deleted handler fails to enforce the target team's manage_team permission before returning deleted-channel metadata. Membership in one team is sufficient to query another team's identifier; the reported exposure is limited to archived public-channel details.

The record

CVE
CVE-2023-47858
Published
Jan 2, 2024
Updated
Jun 17, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-284, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 2, 2024CVE publishedPublication date reported by the CVE source.
  2. Jun 17, 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=0 <=8.1.6
  2. Affected versionversion=0 <=9.0.4
  3. Affected versionversion=0 <=9.1.3
  4. Affected versionversion=0 <=9.2.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=0 <=8.1.6; version=0 <=9.0.4; version=0 <=9.1.3; version=0 <=9.2.2

Published CVSS scores

4.3Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:L/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 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-284Improper Access Control
T1213Data from Information Repositories

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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