Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 7 Mar 2018 07:20:47 -0700
From: Kurt Seifried <>
To: Tomas Hoger <>
Cc: Kurt Seifried <>,
Subject: Re: memcached UDP amplification attacks

Actually the 50k was based on a private but trustworthy reporter (The 3 letter agency people), some people store very big things in memcached like cached web pages...

> On Mar 7, 2018, at 3:09 AM, Tomas Hoger <> wrote:
>> On Fri, 2 Mar 2018 21:42:30 -0700 Kurt Seifried wrote:
>> I have assigned CVE-2018-1000115 to this issue:
>> 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.
> Minor nitpick, the description mentions 1:50,000 ratio, apparently
> based on the information in the following reference:
> where it's mentioned as:
> """
> Worse, memcached can have an amplification factor of over 50,000,
> meaning a 203 byte request results in a 100 megabyte response.
> """
> However, 200 * 50k = 10m, not 100m.  Wonder if I'm doing my math wrong.
> -- 
> Tomas Hoger / Red Hat Product Security

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.