CVE-2011-10020
CVE-2011-10020 is a high-severity vulnerability with a CVSS 4.0 base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 4.0 base score 8.7)
- EPSS exploit prediction: 1% (54th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2011-5257
- Weakness: CWE-20
- Published:
- Last modified:
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.
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 severe is CVE-2011-10020?
- CVE-2011-10020 has a CVSS 4.0 base score of 8.7, rated high severity.
- Is CVE-2011-10020 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2011-10020?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2011-10020 have an EU (EUVD) identifier?
- Yes. CVE-2011-10020 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2011-5257.
- When was CVE-2011-10020 published?
- CVE-2011-10020 was published on 2025-08-20 and last updated on 2026-06-16.
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
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