CVE-2011-10018
myBB 1.6.4 Backdoor Arbitrary Command Execution
CVE-2011-10018 is a critical vulnerability (CVSS 10.0) in Mybb, published August 13, 2025. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 3.02%, the 87th percentile. No source names a fixed version.
- Severity
- 10.0 CriticalCVSS 4.0, CVE List
- Exploit chance
- 3.02%EPSS, 87th percentile
- Exploitation
- None known1 public exploit
- Fixed in
- No fix listedNo source names one
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Metasploit | myBB 1.6.4 Backdoor Arbitrary Command Execution | 2011-10-06 |
What each source reports
CVE List Score used 10.0
myBB 1.6.4 Backdoor Arbitrary Command Execution
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.
- Record
CVE-2011-10018- CVSS 4.0
- 10.0 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Weakness
- CWE-912, CWE-94
- Updated
- 2026-11-02
EUVDEUVD-2011-5246 10.0
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.
- Record
EUVD-2011-5246- CVSS 4.0
- 10.0 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-4whv-mhhp-7qcj 10.0
myBB version 1.6.4 was distributed with an unauthorized backdoor embedded in the source code. The...
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.
- Record
GHSA-4whv-mhhp-7qcj- CVSS 4.0
- 10.0 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-94
- Updated
- 2026-11-02
NVD 10.0
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.
- Record
CVE-2011-10018- CVSS 4.0
- 10.0 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-94, CWE-912
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, Metasploit, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/mybb_backdoor.rb
exploit-db.com/exploits/17949
web.archive.org/web/20111015224948/http://secunia.com/advisories/46300
blog.mybb.com/2011/10/06/1-6-4-security-vulnerabilit
vulncheck.com/advisories/mybb-backdoor-arbitrary-command-execution
nvd.nist.gov/vuln/detail/CVE-2011-10018
github.com/advisories/GHSA-4whv-mhhp-7qcj