XenForo < 2.3.13 XSS via Dynamic Redirect Handler
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 5.1epss 0.3%
exploitation probability
0.3%top 79% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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.
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
Affected products
XenForo · XenForopublic PoCs found — 1
cve_referencegithub.com/BomboBombone/CVE-2026-73319★ 0⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://bombobombone.github.io/posts/cve-2026-73319/https://github.com/BomboBombone/CVE-2026-73319https://www.vulncheck.com/advisories/xenforo-xss-via-dynamic-redirect-handlerhttps://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/