CVE-2026-9162 - Vulnerability Details - OpenCVE

Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Mattermost	Mattermost

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products
Mattermost	Mattermost

References

Link	Providers
https://mattermost.com/security-updates

History

Mon, 22 Jun 2026 16:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Mattermost Mattermost mattermost
Vendors & Products		Mattermost Mattermost mattermost
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 22 Jun 2026 13:45:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664
Title		Global session revocation does not invalidate active WebSocket connections
Weaknesses		CWE-613
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-06-22T13:36:43.998Z

Updated: 2026-06-22T15:40:07.851Z

Reserved: 2026-05-21T11:17:28.560Z

Link: CVE-2026-9162

Vulnrichment

Updated: 2026-06-22T15:40:00.175Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-06-22T16:15:16Z

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-9162", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "state": "PUBLISHED", "assignerShortName": "Mattermost", "dateReserved": "2026-05-21T11:17:28.560Z", "datePublished": "2026-06-22T13:36:43.998Z", "dateUpdated": "2026-06-22T15:40:07.851Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "Mattermost", "vendor": "Mattermost", "versions": [{"lessThanOrEqual": "11.7.0", "status": "affected", "version": "11.7.0", "versionType": "semver"}, {"lessThanOrEqual": "11.6.2", "status": "affected", "version": "11.6.0", "versionType": "semver"}, {"lessThanOrEqual": "11.5.5", "status": "affected", "version": "11.5.0", "versionType": "semver"}, {"lessThanOrEqual": "10.11.17", "status": "affected", "version": "10.11.0", "versionType": "semver"}, {"version": "11.8.0", "status": "unaffected"}, {"version": "11.7.1", "status": "unaffected"}, {"version": "11.6.3", "status": "unaffected"}, {"version": "11.5.6", "status": "unaffected"}, {"version": "10.11.18", "status": "unaffected"}]}], "credits": [{"lang": "en", "type": "finder", "value": "winfunc"}], "descriptions": [{"lang": "en", "value": "Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664"}], "metrics": [{"cvssV3_1": {"attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE", "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N", "baseSeverity": "MEDIUM", "baseScore": 4.3}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "description": "CWE-613: Insufficient Session Expiration", "cweId": "CWE-613"}]}], "references": [{"url": "https://mattermost.com/security-updates", "name": "MMSA-2026-00664", "tags": ["vendor-advisory"]}], "solutions": [{"value": "Update Mattermost to versions 11.8.0, 11.7.1, 11.6.3, 11.5.6, 10.11.18 or higher.", "lang": "en"}], "source": {"advisory": "MMSA-2026-00664", "defect": ["https://mattermost.atlassian.net/browse/MM-68542"], "discovery": "EXTERNAL"}, "title": "Global session revocation does not invalidate active WebSocket connections", "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2026-06-22T13:36:43.998Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-06-22T15:39:54.095237Z", "id": "CVE-2026-9162", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-22T15:40:07.851Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-9162", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-22T15:39:54.095237Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-22T15:40:00.175Z"}}], "cna": {"title": "Global session revocation does not invalidate active WebSocket connections", "source": {"defect": ["https://mattermost.atlassian.net/browse/MM-68542"], "advisory": "MMSA-2026-00664", "discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "winfunc"}], "metrics": [{"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Mattermost", "product": "Mattermost", "versions": [{"status": "affected", "version": "11.7.0", "versionType": "semver", "lessThanOrEqual": "11.7.0"}, {"status": "affected", "version": "11.6.0", "versionType": "semver", "lessThanOrEqual": "11.6.2"}, {"status": "affected", "version": "11.5.0", "versionType": "semver", "lessThanOrEqual": "11.5.5"}, {"status": "affected", "version": "10.11.0", "versionType": "semver", "lessThanOrEqual": "10.11.17"}, {"status": "unaffected", "version": "11.8.0"}, {"status": "unaffected", "version": "11.7.1"}, {"status": "unaffected", "version": "11.6.3"}, {"status": "unaffected", "version": "11.5.6"}, {"status": "unaffected", "version": "10.11.18"}], "defaultStatus": "unaffected"}], "solutions": [{"lang": "en", "value": "Update Mattermost to versions 11.8.0, 11.7.1, 11.6.3, 11.5.6, 10.11.18 or higher."}], "references": [{"url": "https://mattermost.com/security-updates", "name": "MMSA-2026-00664", "tags": ["vendor-advisory"]}], "x_generator": {"engine": "cvelib 1.8.0"}, "descriptions": [{"lang": "en", "value": "Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664"}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-613", "description": "CWE-613: Insufficient Session Expiration"}]}], "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2026-06-22T13:36:43.998Z"}}}, "cveMetadata": {"cveId": "CVE-2026-9162", "state": "PUBLISHED", "dateUpdated": "2026-06-22T15:40:07.851Z", "dateReserved": "2026-05-21T11:17:28.560Z", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "datePublished": "2026-06-22T13:36:43.998Z", "assignerShortName": "Mattermost"}, "dataVersion": "5.2"}