{"id":"CVE-2026-73319","aliases":["EUVD-2026-72756","GHSA-vggm-cwh9-fm3v"],"status":"published","title":"XenForo \u003c 2.3.13 XSS via Dynamic Redirect Handler","description":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.","severity":{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00412,"percentile":0.35967,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-79"],"published":"2026-09-08T13:19:39Z","modified":"2026-10-01T15:20:37Z","exploits":[{"source":"pocgithub","id":"BomboBombone/CVE-2026-73319","title":"BomboBombone/CVE-2026-73319","date":"2026-09-08","url":"https://github.com/BomboBombone/CVE-2026-73319"}],"products":[{"vendor":"xenforo","product":"xenforo"}],"references":[{"url":"https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/","tags":["vendor-advisory","patch","Release Notes"]},{"url":"https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/","tags":["release-notes","Release Notes"]},{"url":"https://bombobombone.github.io/posts/cve-2026-73319/","tags":["technical-description","Exploit","Third Party Advisory"]},{"url":"https://github.com/BomboBombone/CVE-2026-73319","tags":["exploit","Exploit","Third Party Advisory"]},{"url":"https://www.vulncheck.com/advisories/xenforo-xss-via-dynamic-redirect-handler","tags":["third-party-advisory","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-73319"},{"url":"https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856"},{"url":"https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857"},{"url":"https://bombobombone.github.io/posts/cve-2026-73319"},{"url":"https://github.com/advisories/GHSA-vggm-cwh9-fm3v"}],"sources":{"cve":[{"id":"CVE-2026-73319","title":"XenForo \u003c 2.3.13 XSS via Dynamic Redirect Handler","description":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.","status":"published","published":"2026-09-08T13:19:39.156Z","modified":"2026-10-01T15:20:37.963Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T13:43:22.599321Z"}],"euvd":[{"id":"EUVD-2026-72756","description":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.","status":"published","published":"2026-09-08T13:19:39Z","modified":"2026-10-01T15:20:37Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T17:27:45.017929Z"}],"ghsa":[{"id":"GHSA-vggm-cwh9-fm3v","title":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect...","description":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.","status":"published","published":"2026-09-08T15:31:55Z","modified":"2026-09-09T03:30:36Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:11:37.523128Z"}],"nvd":[{"id":"CVE-2026-73319","description":"XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.","status":"published","published":"2026-09-08T14:17:26.333Z","modified":"2026-09-11T20:26:33.74Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:44.436435Z"}]}}