CVE-2011-10020

Kaillera 0.86 Server DoS via Malformed UDP Packet

CVSS 8.7 HIGHEPSS 0.9%CWE-20

Vexday Risk Score

36Attention

SSVC decision (CISA)

Attend

PoC available → attend closely

CVSS 8.7EPSS 0.9%KEV nãoPoC —Nuclei —Metasploit simPatch —

Lifecycle

02 Jul 2011Metasploit module available

20 Aug 2025Published on NVD

Recommendation: Plan a near-term fix — a public PoC already exists.

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.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Affected products

Kaillera Project · Server

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