CVE-2023-50333Network attack vector

Group renaming via stale session roles

Published Jan 2, 2024 · Updated Jun 17, 2025

Improper access control in Mattermost 8.1.6 and earlier and 9.2.2 and earlier allows remote authenticated users to rename groups. The session-demotion path updates the guest flag but leaves existing session roles unchanged, so authorization continues to use stale non-guest permissions. Exploitation requires an authenticated session to remain active while an administrator demotes that account; the stale session can then alter stored group names.

CVSS severity3.7
Low
EPSS probability0.32%
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 8.1.6 and earlier and 9.2.2 and earlier allows remote authenticated users to rename groups. The session-demotion path updates the guest flag but leaves existing session roles unchanged, so authorization continues to use stale non-guest permissions. Exploitation requires an authenticated session to remain active while an administrator demotes that account; the stale session can then alter stored group names.

The record

CVE
CVE-2023-50333
Published
Jan 2, 2024
Updated
Jun 17, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-284, T1565.001
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 <=9.2.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

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

Published CVSS scores

4.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
3.7Mattermost, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/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.

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-284Improper Access Control
T1565.001Stored Data Manipulation

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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