CVE-2011-10018
9.8
CRITICAL · CVSS 3.1 · EPSS 2.8% (pctl 86)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
Description
myBB version 1.6.4 was distributed with an unauthorized backdoor embedded in the source code. The backdoor allowed remote attackers to execute arbitrary PHP code by injecting payloads into a specially crafted collapsed cookie. This vulnerability was introduced during packaging and was not part of the intended application logic. Exploitation requires no authentication and results in full compromise of the web server under the context of the web application.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 2.83% — more likely to be exploited than 86% of all CVEs |
| Weakness | CWE-94 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2025-08-13 |
| Last modified | 2026-06-16 |
Affected (1)
| Vendor | Product |
|---|---|
| mybb | mybb |
References
- https://blog.mybb.com/2011/10/06/1-6-4-security-vulnerabilit/
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/mybb_backdoor.rb
- https://web.archive.org/web/20111015224948/http://secunia.com/advisories/46300/
- https://www.exploit-db.com/exploits/17949
- https://www.vulncheck.com/advisories/mybb-backdoor-arbitrary-command-execution
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/mybb_backdoor.rb
- https://www.exploit-db.com/exploits/17949
→ the Explorer · watch your stack · NVD