{"id":"CVE-2020-15139","details":"In MyBB before version 1.8.24, the custom MyCode (BBCode) for the visual editor doesn't escape input properly when rendering HTML, resulting in a DOM-based XSS vulnerability. The weakness can be exploited by pointing a victim to a page where the visual editor is active (e.g. as a post or Private Message) and operates on a maliciously crafted MyCode message. This may occur on pages where message content is pre-filled using a GET/POST parameter, or on reply pages where a previously saved malicious message is quoted. After upgrading MyBB to 1.8.24, make sure to update the version attribute in the `codebuttons` template for non-default themes to serve the latest version of the patched `jscripts/bbcodes_sceditor.js` file.","aliases":["GHSA-37h7-vfv6-f8rj"],"modified":"2026-07-08T05:59:52.137464281Z","published":"2020-08-10T22:15:14.223Z","database_specific":{"unresolved_ranges":[{"source":"CPE_RANGE","vendor_product":"mybb:mybb","cpes":["cpe:2.3:a:mybb:mybb:*:*:*:*:*:*:*:*"],"extracted_events":[{"fixed":"1.8.24"}]},{"extracted_events":[{"fixed":"1.8.24"}],"source":"DESCRIPTION"}]},"references":[{"type":"FIX","url":"https://github.com/mybb/mybb/commit/37ad29dcd25489a37bdd89ebac761f22492558b0"},{"type":"FIX","url":"https://github.com/mybb/mybb/security/advisories/GHSA-37h7-vfv6-f8rj"},{"type":"FIX","url":"https://mybb.com/versions/1.8.24/"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/mybb/mybb","events":[{"introduced":"0"},{"fixed":"37ad29dcd25489a37bdd89ebac761f22492558b0"}],"database_specific":{"source":"REFERENCES"}}],"versions":["mybb_1823_build","mybb_1823","mybb_1822","mybb_1822_build","mybb_1821pl1","mybb_1821","mybb_1821_build","mybb_1817_build","mybb_1817","mybb_1820","mybb_1820_build","mybb_1820-rc","mybb_1819","mybb_1818","mybb_1819_build","mybb_1818_build","mybb_1816","mybb_1816_build","mybb_1815","mybb_1815_build","mybb_1814","mybb_1813","mybb_1812","mybb_1811","mybb_1810","mybb_1809","mybb_1808","mybb_1807","mybb_1806","mybb_1805","mybb_1804","mybb_1800","mybb_1801"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-15139.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}