CVE-2026-4055

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-4055", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "state": "PUBLISHED", "assignerShortName": "Mattermost", "dateReserved": "2026-03-12T16:09:11.995Z", "datePublished": "2026-05-21T07:13:31.669Z", "dateUpdated": "2026-05-21T12:39:35.248Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "Mattermost", "vendor": "Mattermost", "versions": [{"lessThanOrEqual": "11.5.1", "status": "affected", "version": "11.5.0", "versionType": "semver"}, {"version": "11.6.0", "status": "unaffected"}, {"version": "11.5.2", "status": "unaffected"}, {"version": "10.11.14", "status": "unaffected"}, {"version": "11.4.4", "status": "unaffected"}]}], "credits": [{"lang": "en", "type": "finder", "value": "0x7oda7123"}], "descriptions": [{"lang": "en", "value": "Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629"}], "metrics": [{"cvssV3_1": {"attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "NONE", "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "baseSeverity": "MEDIUM", "baseScore": 4.3}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "description": "CWE-863: Incorrect Authorization", "cweId": "CWE-863"}]}], "references": [{"url": "https://mattermost.com/security-updates", "name": "MMSA-2026-00629", "tags": ["vendor-advisory"]}], "solutions": [{"value": "Update Mattermost to versions 11.6.0, 11.5.2, 10.11.14, 11.4.4 or higher.", "lang": "en"}], "source": {"advisory": "MMSA-2026-00629", "defect": ["https://mattermost.atlassian.net/browse/MM-67858"], "discovery": "EXTERNAL"}, "title": "Insufficient permission validation on cross-team playbook run creation", "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2026-05-21T07:13:31.669Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-05-21T12:39:26.946775Z", "id": "CVE-2026-4055", "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": "2026-05-21T12:39:35.248Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-4055", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-05-21T12:39:26.946775Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-21T12:39:30.978Z"}}], "cna": {"title": "Insufficient permission validation on cross-team playbook run creation", "source": {"defect": ["https://mattermost.atlassian.net/browse/MM-67858"], "advisory": "MMSA-2026-00629", "discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "0x7oda7123"}], "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:N/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Mattermost", "product": "Mattermost", "versions": [{"status": "affected", "version": "11.5.0", "versionType": "semver", "lessThanOrEqual": "11.5.1"}, {"status": "unaffected", "version": "11.6.0"}, {"status": "unaffected", "version": "11.5.2"}, {"status": "unaffected", "version": "10.11.14"}, {"status": "unaffected", "version": "11.4.4"}], "defaultStatus": "unaffected"}], "solutions": [{"lang": "en", "value": "Update Mattermost to versions 11.6.0, 11.5.2, 10.11.14, 11.4.4 or higher."}], "references": [{"url": "https://mattermost.com/security-updates", "name": "MMSA-2026-00629", "tags": ["vendor-advisory"]}], "x_generator": {"engine": "cvelib 1.8.0"}, "descriptions": [{"lang": "en", "value": "Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629"}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-863", "description": "CWE-863: Incorrect Authorization"}]}], "providerMetadata": {"orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "shortName": "Mattermost", "dateUpdated": "2026-05-21T07:13:31.669Z"}}}, "cveMetadata": {"cveId": "CVE-2026-4055", "state": "PUBLISHED", "dateUpdated": "2026-05-21T12:39:35.248Z", "dateReserved": "2026-03-12T16:09:11.995Z", "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee", "datePublished": "2026-05-21T07:13:31.669Z", "assignerShortName": "Mattermost"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Mattermost", "vendor": "Mattermost", "versions": [{"lessThanOrEqual": "11.5.1", "status": "affected", "version": "11.5.0", "versionType": "semver"}, {"status": "unaffected", "version": "11.6.0"}, {"status": "unaffected", "version": "11.5.2"}, {"status": "unaffected", "version": "10.11.14"}, {"status": "unaffected", "version": "11.4.4"}]}], "source": "responsibledisclosure@mattermost.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "F9018E52-5C7F-4E59-B637-604B8EECD974", "versionEndExcluding": "10.11.17", "versionStartIncluding": "10.11.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "DF287562-A912-43DD-8FAC-0CD8EC7BEF7E", "versionEndExcluding": "11.5.5", "versionStartIncluding": "11.5.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "AFCFC389-02A5-45CD-8EEB-9ED208C0EE83", "versionEndExcluding": "11.6.2", "versionStartIncluding": "11.6.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629"}, {"lang": "es", "value": "Las versiones de Mattermost 11.5.x <= 11.5.1 fallan al validar el permiso run_create a nivel de equipo contra el equipo de destino al crear una ejecuci\u00f3n de playbook, lo que permite a un miembro del equipo autenticado crear ejecuciones en equipos donde carecen de permiso mediante la especificaci\u00f3n de un ID de equipo diferente en la solicitud de API de creaci\u00f3n de ejecuci\u00f3n. ID de Aviso de Mattermost: MMSA-2026-00629"}], "id": "CVE-2026-4055", "lastModified": "2026-07-23T16:10:00.137", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "responsibledisclosure@mattermost.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-4055", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-21T12:39:26.946775Z", "version": "2.0.3"}}]}, "published": "2026-05-21T08:16:23.130", "references": [{"source": "responsibledisclosure@mattermost.com", "tags": ["Vendor Advisory"], "url": "https://mattermost.com/security-updates"}], "sourceIdentifier": "responsibledisclosure@mattermost.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-863"}], "source": "responsibledisclosure@mattermost.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[11.5.0,11.5.1]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "11.6.0"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "11.5.2"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "10.11.14"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "11.4.4"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Mattermost", "source": "cna", "vendor": "Mattermost"}, "product": "mattermost", "vendor": "mattermost"}], "created": "2026-05-21T08:30:05.939263+00:00", "updated": "2026-05-21T08:30:06.256076+00:00", "vendors": ["mattermost", "mattermost$PRODUCT$mattermost"]}