{"id":"CVE-2018-21259","aliases":["EUVD-2018-13774","GHSA-w5xj-4h4h-82v2"],"status":"published","title":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers...","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.01096,"percentile":0.65827,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-20"],"published":"2020-06-19T16:47:10Z","modified":"2026-10-24T10:30:36Z","products":[{"vendor":"mattermost","product":"mattermost_server"}],"references":[{"url":"https://mattermost.com/security-updates/","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-21259"},{"url":"https://github.com/advisories/GHSA-w5xj-4h4h-82v2"}],"sources":{"cve":[{"id":"CVE-2018-21259","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","status":"published","published":"2020-06-19T16:47:10Z","modified":"2024-08-05T12:26:39.575Z","updated_at":"2026-11-02T14:35:02.289647Z"}],"euvd":[{"id":"EUVD-2018-13774","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","status":"published","published":"2020-06-19T16:47:10Z","modified":"2024-08-05T12:26:39Z","updated_at":"2026-11-03T02:39:27.875919Z"}],"ghsa":[{"id":"GHSA-w5xj-4h4h-82v2","title":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers...","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","status":"published","published":"2022-05-24T17:21:09Z","modified":"2023-01-29T05:03:06Z","updated_at":"2026-11-02T14:45:14.655741Z"}],"nvd":[{"id":"CVE-2018-21259","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","status":"published","published":"2020-06-19T17:15:12.85Z","modified":"2026-06-17T01:54:29.22Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:05:00.03074Z"}],"osv":[{"id":"CVE-2018-21259","description":"An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.","status":"published","published":"2020-06-19T17:15:12.85Z","modified":"2026-10-24T10:30:36.428820181Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T15:44:09.145458Z"}]}}