CVE-2011-10018: mybb Code Injection — Exploit & Fix

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.

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CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-94 CWE-94

CWE-912 CWE-912

Affected Products

Vendor	Product	Versions
mybb	mybb	All

References

Advisories & Patches

https://blog.mybb.com/2011/10/06/1-6-4-security-vulnerabilit/

Exploits

https://www.exploit-db.com/exploits/17949 https://www.exploit-db.com/exploits/17949

Other References

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.vulncheck.com/advisories/mybb-backdoor-arbitrary-command-execution https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/mybb_backdoor.rb

Frequently Asked Questions

What is CVE-2011-10018? +

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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2011-10018? +

CVE-2011-10018 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2011-10018? +

CVE-2011-10018 affects products from mybb, specifically: mybb. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2011-10018? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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