CVE-2018-25250 MyBB CVE debrief

Who should care

Users of MyBB with the Last User's Threads in Profile Plugin version 1.2 should apply patches or mitigations to prevent exploitation. This includes administrators and security teams responsible for MyBB installations, as well as operators and platform managers who may be impacted by the vulnerability. Vulnerability management and security teams should review the CVE and NVD details to assess the potential impact on their systems and plan accordingly.

Technical summary

CVE-2018-25250 is a persistent cross-site scripting vulnerability in MyBB's Last User's Threads in Profile Plugin version 1.2. Attackers can inject malicious scripts by crafting thread subjects with script tags, which execute when users visit the attacker's profile page. The vulnerability has a CVSS score of 5.1, indicating a medium severity. The vulnerability affects MyBB users with the Last User's Threads in Profile Plugin version 1.2. Defensive measures include applying patches or updates for MyBB's Last User's Threads in Profile Plugin to version 1.3 or later, implementing input validation and output encoding for user-supplied data, and monitoring for suspicious activity on MyBB profiles and threads.

Defensive priority

Medium priority due to the CVSS score of 5.1 and the potential for attackers to inject malicious scripts.

Recommended defensive actions

• Apply patches or updates for MyBB's Last User's Threads in Profile Plugin to version 1.3 or later
• Implement input validation and output encoding for user-supplied data
• Monitor for suspicious activity on MyBB profiles and threads
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD detail provide information on the vulnerability, but further analysis is needed to determine the full scope of affected systems and potential mitigations. The Last User's Threads in Profile Plugin version 1.2 for MyBB contains a persistent cross-site scripting vulnerability. Attackers can inject malicious scripts by crafting thread subjects with script tags, which execute when users visit the attacker's profile page. Evidence is limited to CVE and NVD details, and defenders should verify MyBB configurations and user interactions.

Official resources