{"id":"CVE-2017-18873","aliases":["GHSA-x6mw-hf2j-vqpc","GO-2026-4282"],"url":"https://o3.security/vulnerability/CVE-2017-18873","summary":"Mattermost Server is vulnerable to channel invisibility DoS via misformatted post","details":"An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to cause a denial of service (channel invisibility) via a misformatted post.","published":"2020-06-19T18:15:10.600Z","modified":"2026-08-27T08:18:56.844279Z","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":{"score":0.01096,"percentile":0.62589,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.1.2-0.20171013141717-ee57a5829ab1"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.2.1-0.20171013140502-b3e4b0ac9168"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.3.0"}],"fix":{"url":"https://github.com/mattermost/mattermost/commit/9adaf53e110e0e806b21903111aacb93129668cb","label":"mattermost/mattermost@9adaf53"},"references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates/"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2017-18873"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/9adaf53e110e0e806b21903111aacb93129668cb"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/b3e4b0ac91682093276a653f7ccd5774aaa9cd06"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/ee57a5829ab162859e0e355dac6cfe6ca1a8f379"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"},{"type":"WEB","url":"https://mattermost.com/security-updates"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-27T08:18:56.844279Z"}}