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Sid 1-47724

Message

SERVER-OTHER Memcached DDoS attempt

Summary

This event is generated when Memcached is being targeted by a DDoS/information discovery attempt.

Impact

Attempted Denial of Service

CVE-2018-1000115:

CVSS base score 7.5

CVSS impact score 3.6

CVSS exploitability score 3.9

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Detailed information

CVE-2018-1000115: Memcached version 1.5.5 contains an Insufficient Control of Network Message Volume (Network Amplification, CWE-406) vulnerability in the UDP support of the memcached server that can result in denial of service via network flood (traffic amplification of 1:50,000 has been reported by reliable sources). This attack appear to be exploitable via network connectivity to port 11211 UDP. This vulnerability appears to have been fixed in 1.5.6 due to the disabling of the UDP protocol by default.

Affected systems

  • memcached memcached 1.5.5
  • canonical ubuntu_linux 14.04
  • canonical ubuntu_linux 16.04
  • canonical ubuntu_linux 17.10

Ease of attack

CVE-2018-1000115:

Access Vector

Access Complexity

Authentication

False positives

False negatives

Corrective action

Contributors

  • Cisco's Talos Intelligence Group

Additional References

  • blog.cloudflare.com/memcrashed-major-amplification-attacks-from-port-11211/