CVE-2026-0997Network attack vector

Authenticated restriction changes via unverified payload user ID

Published Feb 16, 2026 · Updated Feb 16, 2026

Incorrect authorization in Mattermost Zoom Plugin before 1.11.0 allows remote authenticated users to alter arbitrary channel restrictions. The handleChannelPreference handler uses SubmitDialogRequest.UserId from the request body for its ManageSystem permission check and settings write without binding it to the authenticated Mattermost-User-Id header. Any logged-in user can submit an authorized user's ID and change whether Zoom meetings are permitted in arbitrary channels; confidentiality and availability are unaffected.

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

What happened

Incorrect authorization in Mattermost Zoom Plugin before 1.11.0 allows remote authenticated users to alter arbitrary channel restrictions. The handleChannelPreference handler uses SubmitDialogRequest.UserId from the request body for its ManageSystem permission check and settings write without binding it to the authenticated Mattermost-User-Id header. Any logged-in user can submit an authorized user's ID and change whether Zoom meetings are permitted in arbitrary channels; confidentiality and availability are unaffected.

The record

CVE
CVE-2026-0997
Published
Feb 16, 2026
Updated
Feb 16, 2026
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-863, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 16, 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=10.11.0 <=10.11.9
  2. Affected versionversion=11.1.0 <=11.1.2
  3. Affected versionversion=11.2.0 <=11.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=10.11.0 <=10.11.9; version=11.1.0 <=11.1.2; version=11.2.0 <=11.2.1

Published CVSS scores

4.3Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
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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