CVE-2025-12689 - Vulnerability Details - OpenCVE

Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

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

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

Update Mattermost to versions 11.1.0, 11.0.5, 10.12.3, 10.11.7 or higher.

Workaround

No workaround given by the vendor.

References

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

History

Wed, 17 Dec 2025 20:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 17 Dec 2025 18:30:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.
Title		DoS in Calls plugin via malformed UTF-8 in WebSocket request
Weaknesses		CWE-1287
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}`

Projects

Sign in to view the affected projects.

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2025-12-17T18:14:10.973Z

Updated: 2025-12-17T19:29:54.734Z

Reserved: 2025-11-04T10:06:23.912Z

Link: CVE-2025-12689

Vulnrichment

Updated: 2025-12-17T18:52:42.809Z

NVD

Status : Received

Published: 2025-12-17T19:16:00.537

Modified: 2025-12-17T19:16:00.537

Link: CVE-2025-12689

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-1287

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-12689", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "state": "PUBLISHED", "assignerShortName": "Mattermost", "dateReserved": "2025-11-04T10:06:23.912Z", "datePublished": "2025-12-17T18:14:10.973Z", "dateUpdated": "2025-12-17T19:29:54.734Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "Mattermost", "vendor": "Mattermost", "versions": [{"lessThanOrEqual": "11.0.4", "status": "affected", "version": "11.0.0", "versionType": "semver"}, {"lessThanOrEqual": "10.12.2", "status": "affected", "version": "10.12.0", "versionType": "semver"}, {"lessThanOrEqual": "10.11.6", "status": "affected", "version": "10.11.0", "versionType": "semver"}, {"status": "unaffected", "version": "11.1.0"}, {"status": "unaffected", "version": "11.0.5"}, {"status": "unaffected", "version": "10.12.3"}, {"status": "unaffected", "version": "10.11.7"}]}], "credits": [{"lang": "en", "type": "finder", "value": "National Security Agency"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.</p>"}], "value": "Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request."}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-1287", "description": "CWE-1287: Improper Validation of Specified Type of Input", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2025-12-17T18:14:10.973Z"}, "references": [{"url": "https://mattermost.com/security-updates"}], "solutions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>Update Mattermost to versions 11.1.0, 11.0.5, 10.12.3, 10.11.7 or higher.</p>"}], "value": "Update Mattermost to versions 11.1.0, 11.0.5, 10.12.3, 10.11.7 or higher."}], "source": {"advisory": "MMSA-2025-00539", "defect": ["https://mattermost.atlassian.net/browse/MM-66169"], "discovery": "EXTERNAL"}, "title": "DoS in Calls plugin via malformed UTF-8 in WebSocket request", "x_generator": {"engine": "Vulnogram 0.5.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2025-12-17T18:52:40.079447Z", "id": "CVE-2025-12689", "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": "2025-12-17T19:29:54.734Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-12689", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2025-12-17T18:52:40.079447Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-12-17T18:52:42.809Z"}}], "cna": {"title": "DoS in Calls plugin via malformed UTF-8 in WebSocket request", "source": {"defect": ["https://mattermost.atlassian.net/browse/MM-66169"], "advisory": "MMSA-2025-00539", "discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "National Security Agency"}], "metrics": [{"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Mattermost", "product": "Mattermost", "versions": [{"status": "affected", "version": "11.0.0", "versionType": "semver", "lessThanOrEqual": "11.0.4"}, {"status": "affected", "version": "10.12.0", "versionType": "semver", "lessThanOrEqual": "10.12.2"}, {"status": "affected", "version": "10.11.0", "versionType": "semver", "lessThanOrEqual": "10.11.6"}, {"status": "unaffected", "version": "11.1.0"}, {"status": "unaffected", "version": "11.0.5"}, {"status": "unaffected", "version": "10.12.3"}, {"status": "unaffected", "version": "10.11.7"}], "defaultStatus": "unaffected"}], "solutions": [{"lang": "en", "value": "Update Mattermost to versions 11.1.0, 11.0.5, 10.12.3, 10.11.7 or higher.", "supportingMedia": [{"type": "text/html", "value": "<p>Update Mattermost to versions 11.1.0, 11.0.5, 10.12.3, 10.11.7 or higher.</p>", "base64": false}]}], "references": [{"url": "https://mattermost.com/security-updates"}], "x_generator": {"engine": "Vulnogram 0.5.0"}, "descriptions": [{"lang": "en", "value": "Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.", "supportingMedia": [{"type": "text/html", "value": "<p>Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.</p>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-1287", "description": "CWE-1287: Improper Validation of Specified Type of Input"}]}], "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2025-12-17T18:14:10.973Z"}}}, "cveMetadata": {"cveId": "CVE-2025-12689", "state": "PUBLISHED", "dateUpdated": "2025-12-17T19:29:54.734Z", "dateReserved": "2025-11-04T10:06:23.912Z", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "datePublished": "2025-12-17T18:14:10.973Z", "assignerShortName": "Mattermost"}, "dataVersion": "5.2"}