{"id":"CVE-2021-23838","aliases":["EUVD-2021-10766","GHSA-w58h-cm85-98cc"],"status":"published","title":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was...","description":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.","severity":{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.00993,"percentile":0.6305,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2021-01-15T06:27:45Z","modified":"2026-06-17T03:38:54Z","products":[{"vendor":"flatcore","product":"flatcore"}],"references":[{"url":"https://github.com/flatCore/flatCore-CMS","tags":["x_refsource_MISC","x_transferred","Product","Third Party Advisory"]},{"url":"https://sec-consult.com/vulnerability-lab/","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"http://packetstormsecurity.com/files/160936/flatCore-CMS-XSS-File-Disclosure-SQL-Injection.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-23838"},{"url":"https://github.com/advisories/GHSA-w58h-cm85-98cc"}],"sources":{"cve":[{"id":"CVE-2021-23838","description":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.","status":"published","published":"2021-01-15T06:27:45Z","modified":"2024-08-03T19:14:09.152Z","updated_at":"2026-11-02T14:33:00.488332Z"}],"euvd":[{"id":"EUVD-2021-10766","description":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.","status":"published","published":"2021-01-15T06:27:45Z","modified":"2024-08-03T19:14:09Z","updated_at":"2026-11-03T03:25:00.126172Z"}],"ghsa":[{"id":"GHSA-w58h-cm85-98cc","title":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was...","description":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.","status":"published","published":"2022-05-24T17:39:23Z","modified":"2023-01-29T05:05:25Z","cwes":["CWE-79"],"updated_at":"2026-11-02T14:45:47.324105Z"}],"nvd":[{"id":"CVE-2021-23838","description":"An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.","status":"published","published":"2021-01-15T07:15:14.143Z","modified":"2026-06-17T03:38:54.327Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":3.5,"vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:06:49.284888Z"}]}}