CVE-2011-10020: Input Validation Flaw

Description

Kaillera Server version 0.86 is vulnerable to a denial-of-service condition triggered by sending a malformed UDP packet after the initial handshake. Once a client sends a valid HELLO0.83 packet and receives a response, any subsequent malformed packet causes the server to crash and become unresponsive. This flaw stems from improper input validation in the server’s UDP packet handler, allowing unauthenticated remote attackers to disrupt service availability.

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Weakness Type (CWE)

CWE-20 Improper Input Validation

References

Other References

http://kaillera.com/ https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/auxiliary/dos/windows/games/kaillera.rb https://www.exploit-db.com/exploits/17460 https://www.vulncheck.com/advisories/kaillera-server-dos-via-malformed-udp-packet https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/auxiliary/dos/windows/games/kaillera.rb https://www.exploit-db.com/exploits/17460

Frequently Asked Questions

What is CVE-2011-10020? +

Kaillera Server version 0.86 is vulnerable to a denial-of-service condition triggered by sending a malformed UDP packet after the initial handshake. Once a client sends a valid HELLO0.83 packet and receives a response, any subsequent malformed packet causes the server to crash and become unresponsive. This flaw stems from improper input validation in the server’s UDP packet handler, allowing unauthenticated remote attackers to disrupt service availability.

How do I check if I'm vulnerable to CVE-2011-10020? +

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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CVE-2011-10020