{"id":24914,"date":"2026-09-17T04:32:07","date_gmt":"2026-09-16T20:32:07","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-85386"},"modified":"2026-09-17T04:32:07","modified_gmt":"2026-09-16T20:32:07","slug":"cve-2026-85386","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-85386","title":{"rendered":"CVE-2026-85386 &#8211; Concrete CMS before 9.5.4 did not sanitize XML and XSLT documents uploaded through a publi"},"content":{"rendered":"<p>Concrete CMS before 9.5.4 did not sanitize XML and XSLT documents uploaded through a public Form Block file-upload question. Plain XML uploads were validated by file extension only and stored as publicly accessible files that were served inline from the application&#8217;s own origin. An unauthenticated visitor could therefore store an XML document containing an xml-stylesheet processing instruction that referenced an attacker-supplied, same-origin XSLT stylesheet. When a victim opened the stored file directly in a browser, the browser fetched the stylesheet, transformed the document into HTML, and executed attacker-controlled JavaScript in the Concrete CMS origin (stored cross-site scripting). If the victim was an authenticated administrator, the script could act with that administrator&#8217;s session, and the reporter demonstrated creation of a new user in the Administrators group.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.3 with vector CVSS:4.0\/AV:N\/AC:L\/AT:P\/PR:L\/UI:A\/VC:H\/VI:H\/VA:H\/SC:N\/SI:N\/SA:N. Thanks Valentin SARRE (Independent security researcher) for reporting.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Concrete CMS before 9.5.4 did not sanitize XML and XSLT documents uploaded through a public Form Block file-upload question. Plain XML uploads were validated by file extension only and stored as publi<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-24914","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/24914","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=24914"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=24914"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=24914"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}