{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93849","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","state":"PUBLISHED","assignerShortName":"Mattermost","dateReserved":"2026-09-18T18:40:09.913Z","datePublished":"2026-10-26T14:25:26.554Z","dateUpdated":"2026-10-26T16:46:45.736Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Mattermost","vendor":"Mattermost","versions":[{"lessThanOrEqual":"11.9.1","status":"affected","version":"11.9.0","versionType":"semver"},{"lessThanOrEqual":"11.8.5","status":"affected","version":"11.8.0","versionType":"semver"},{"lessThanOrEqual":"11.7.10","status":"affected","version":"11.7.0","versionType":"semver"},{"lessThanOrEqual":"11.10.1","status":"affected","version":"11.10.0","versionType":"semver"},{"version":"11.11.0","status":"unaffected"},{"version":"11.9.2","status":"unaffected"},{"version":"11.8.6","status":"unaffected"},{"version":"11.7.11","status":"unaffected"},{"version":"11.10.2","status":"unaffected"}]}],"credits":[{"lang":"en","type":"finder","value":"oduoke"}],"descriptions":[{"lang":"en","value":"Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 Mattermost fail to apply allocation limits to the byte-string decode paths in its WebSocket msgpack decoder, which allows an authenticated remote attacker to cause excessive server memory allocation via a crafted binary WebSocket frame declaring a Bin32 payload length of up to 4,294,967,295 bytes.. Mattermost Advisory ID: MMSA-2026-00768"}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseSeverity":"MEDIUM","baseScore":6.5},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","description":"CWE-789: Memory Allocation with Excessive Size Value","cweId":"CWE-789"}]}],"references":[{"url":"https://mattermost.com/security-updates","name":"MMSA-2026-00768","tags":["vendor-advisory"]}],"solutions":[{"value":"Update Mattermost to versions 11.11.0, 11.9.2, 11.8.6, 11.7.11, 11.10.2 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2026-00768","defect":["https://mattermost.atlassian.net/browse/MM-70173"],"discovery":"EXTERNAL"},"title":"Mattermost allows authenticated users to trigger excessive memory allocation via crafted msgpack binary WebSocket frames","providerMetadata":{"orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","shortName":"Mattermost","dateUpdated":"2026-10-26T14:25:26.554Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-93849","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-26T15:32:42.705205Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-10-26T16:46:45.736Z"}}]}}