{"id":"CVE-2017-18898","aliases":["GHSA-9589-mq83-f749","GO-2026-4300"],"url":"https://o3.security/vulnerability/CVE-2017-18898","summary":"Mattermost Server is vulnerable to DoS through maliciously crafted posts","details":"An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It allows crafted posts that potentially cause a web browser to hang.","published":"2020-06-19T19:15:11.373Z","modified":"2026-08-27T08:18:59.441395Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.0.5"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.1.1"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.2.0"}],"fix":{"url":"https://github.com/grundleborg/mattermost/commit/5286318c72aa230f33f89df3b4cbdc33a0822a93","label":"grundleborg/mattermost@5286318"},"references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates/"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2017-18898"},{"type":"WEB","url":"https://github.com/grundleborg/mattermost/commit/5286318c72aa230f33f89df3b4cbdc33a0822a93"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/5bf6f06c02c368b9c73a8be2d2d8795b3405b22b"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/5c22176c963a7393241872073547f30083efe218"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"},{"type":"WEB","url":"https://mattermost.com/security-updates"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-27T08:18:59.441395Z"}}