CVE-2018-1000115: High severity Memcached Memcached vulnerability
Last updated 25 August 2025
Other sources
memcached supports TCP and UDP servers, when the UDP server is enabled, and the configuration does not specify localhost or 127.0.0.1, and the server does not firewall the memcached port (11211 by default) can be exploited for network traffic amplification attacks by spoofed UDP packets.
Please note that by default the firewall on Red Hat Enterprise Linux only allows port 22 (SSH) inbound, so systems with memcached enabled are only affected if a firewall rule is added that allows UDP traffic to connect to memcached (by default on port 11211).
— Red Hat
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.
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is CVE-2018-1000115?
CVE-2018-1000115 is a vulnerability in Memcached version 1.5.5 that allows for network flood denial-of-service attacks.
Which software versions are affected by CVE-2018-1000115?
Memcached version 1.5.5 and lower are affected by CVE-2018-1000115.
What is the severity of CVE-2018-1000115?
CVE-2018-1000115 has a severity rating of 7.5 (High).
How can I fix CVE-2018-1000115?
To fix CVE-2018-1000115, update Memcached to version 1.5.6 or higher.
Where can I find more information about CVE-2018-1000115?
You can find more information about CVE-2018-1000115 in the release notes of Memcached version 1.5.6 and the provided references.