CVE-2026-73319 json
XenForo < 2.3.13 XSS via Dynamic Redirect Handler
published 2026-09-08 2 mo ago modified 2026-10-01 39 d ago also EUVD-2026-72756
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 35%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- XenForo XenForo 2.3.13
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 1 mo ago
Exploit prediction
0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/BomboBombone/CVE-2026-73319 referenced PoC, tagged "exploit" by a source, unverified
- bombobombone.github.io https://bombobombone.github.io/posts/cve-2026-73319/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | 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 |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | 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 |
Affected products
- XenForo XenForo
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
xenforo.com
/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/
vendor-advisory, patch, release-notes
-
github.com
/BomboBombone/CVE-2026-73319
exploit, third-party-advisory
-
bombobombone.github.io
/posts/cve-2026-73319/
technical-description, exploit, third-party-advisory
-
xenforo.com
/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/
release-notes
-
vulncheck.com
/advisories/xenforo-xss-via-dynamic-redirect-handler
third-party-advisory
Sources
- CVE List CVE-2026-73319
- NVD CVE-2026-73319
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