{"action":"Upgrade github.com/mattermost/mattermost-server to 4.1.2-0.20171013141717-ee57a5829ab1+incompatible or later.","affected":[{"fixed":"4.1.2-0.20171013141717-ee57a5829ab1+incompatible","introduced":"0"},{"fixed":"4.2.1-0.20171013140502-b3e4b0ac9168+incompatible","introduced":"4.2.0+incompatible"},{"fixed":"4.3.0+incompatible","introduced":"4.3.0-rc1+incompatible"}],"component":"github.com/mattermost/mattermost-server","cve_ids":["CVE-2017-18873"],"ecosystem":"Go","epss":0.01106,"exploited":false,"fixed_versions":["4.1.2-0.20171013141717-ee57a5829ab1+incompatible","4.2.1-0.20171013140502-b3e4b0ac9168+incompatible","4.3.0+incompatible"],"ghsa_id":"GHSA-x6mw-hf2j-vqpc","id":"tcs_01M5KGCW2ACM4VRHAMZ6H80YVX","modified_at":"2026-02-26T18:56:01.453798Z","published_at":"2026-02-26T16:27:46Z","references":["https://osv.dev/vulnerability/GO-2026-4282","https://github.com/advisories/GHSA-x6mw-hf2j-vqpc","https://nvd.nist.gov/vuln/detail/CVE-2017-18873","https://github.com/mattermost/mattermost/commit/9adaf53e110e0e806b21903111aacb93129668cb","https://github.com/mattermost/mattermost/commit/b3e4b0ac91682093276a653f7ccd5774aaa9cd06","https://github.com/mattermost/mattermost/commit/ee57a5829ab162859e0e355dac6cfe6ca1a8f379","https://mattermost.com/security-updates"],"severity":{"label":"unknown"},"sources":[{"source":"osv","source_id":"GO-2026-4282","url":"https://osv.dev/vulnerability/GO-2026-4282"}],"summary":"Mattermost Server is vulnerable to channel invisibility DoS via misformatted post in github.com/mattermost/mattermost-server"}