CVE-2018-25309
MyBB Recent threads 17.0 Persistent Cross-Site Scripting
MEDIUM 5.1EPSS 0.3%
MyBB Recent threads 17.0 contains a persistent cross-site scripting vulnerability that allows attackers to inject malicious scripts by creating threads with crafted subject lines. Attackers can create threads with script tags in the subject parameter to execute arbitrary JavaScript in the browsers of all users viewing the index page.
- Affected
- mybb · MyBB Recent threads
- CVSS v4.0 VULNCHECK
- 5.1 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/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 - CVSS v3.1 NVD
- 6.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS v3.1 VULNCHECK
- 7.2 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N - EPSS
- 0.26% chance of exploitation in the next 30 days, 17th percentile
- Published
- 2026-04-29
- Updated
- 2026-05-24
Proof-of-concept exploits (1)
Security advisories
- https://www.vulncheck.com/advisories/mybb-recent-threads-persistent-cross-site-scripting
- https://community.mybb.com/mods.php?action=view&pid=191