CVE-2025-29459
📋 TL;DR
This CVE describes a Server-Side Request Forgery (SSRF) vulnerability in MyBB 1.8.38's Mail function that could allow attackers to access internal network resources. The vulnerability affects MyBB forum administrators who can use the Mail function. The vendor disputes the severity, citing administrator permissions and existing SSRF mitigations.
💻 Affected Systems
- MyBB
📦 What is this software?
Mybb by Mybb
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains access to sensitive internal systems, exfiltrates data from internal services, or performs internal network reconnaissance.
Likely Case
Limited information disclosure from internal services accessible to the MyBB server, potentially exposing configuration details or metadata.
If Mitigated
Minimal impact if proper network segmentation and SSRF protections are implemented as recommended in MyBB documentation.
🎯 Exploit Status
Exploitation requires administrator-level access to the Mail function. The vulnerability is disputed by the vendor.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available. Follow workarounds and implement SSRF protections as described in MyBB documentation.
🔧 Temporary Workarounds
Implement SSRF Protections
allConfigure MyBB to restrict access to internal hosts and IP addresses as recommended in official documentation.
Restrict Administrator Access
allLimit access to the Mail function to only trusted administrators and implement strong authentication controls.
🧯 If You Can't Patch
- Implement network segmentation to isolate the MyBB server from sensitive internal resources.
- Deploy web application firewall rules to detect and block SSRF attempts.
🔍 How to Verify
Check if Vulnerable:
Check if running MyBB 1.8.38 and review administrator access controls for the Mail function.Check Version:
Check MyBB Admin CP → Version & Update section or review inc/config.php for version information.Verify Fix Applied:
Verify SSRF protections are implemented by testing restricted access to internal resources from the Mail function.📡 Detection & Monitoring
Log Indicators:
- Unusual outbound HTTP requests from the MyBB server to internal IP addresses
- Multiple failed attempts to access restricted resources via the Mail function
Network Indicators:
- HTTP requests from MyBB server to internal services that shouldn't be accessed externally
- Unusual traffic patterns from the forum server to internal network segments
SIEM Query:
source="mybb_logs" AND (url CONTAINS "mail.php" OR action="mail_function") AND (dest_ip IN (RFC1918_IP_RANGES) OR dest_port NOT IN (80,443))