{"action":"Upgrade github.com/mattermost/mattermost-server to 4.0.5+incompatible or later.","affected":[{"fixed":"4.0.5+incompatible","introduced":"0"},{"fixed":"4.1.1+incompatible","introduced":"4.1.0+incompatible"},{"fixed":"4.2.0+incompatible","introduced":"4.2.0-rc1+incompatible"}],"component":"github.com/mattermost/mattermost-server","cve_ids":["CVE-2017-18898"],"ecosystem":"Go","epss":0.01106,"exploited":false,"fixed_versions":["4.0.5+incompatible","4.1.1+incompatible","4.2.0+incompatible"],"ghsa_id":"GHSA-9589-mq83-f749","id":"tcs_01M5KGCYXMH7GC39YNTV31HYC7","modified_at":"2026-03-03T04:57:51.619208Z","published_at":"2026-01-13T16:42:40Z","references":["https://osv.dev/vulnerability/GO-2026-4300","https://github.com/advisories/GHSA-9589-mq83-f749","https://nvd.nist.gov/vuln/detail/CVE-2017-18898","https://github.com/grundleborg/mattermost/commit/5286318c72aa230f33f89df3b4cbdc33a0822a93","https://github.com/mattermost/mattermost/commit/5bf6f06c02c368b9c73a8be2d2d8795b3405b22b","https://github.com/mattermost/mattermost/commit/5c22176c963a7393241872073547f30083efe218","https://mattermost.com/security-updates"],"severity":{"label":"unknown"},"sources":[{"source":"osv","source_id":"GO-2026-4300","url":"https://osv.dev/vulnerability/GO-2026-4300"}],"summary":"Mattermost Server is vulnerable to DoS through maliciously crafted posts in github.com/mattermost/mattermost-server"}