Possible Sudden Uptick in ASA DOS?

Thu Jul 9 14:11:56 UTC 2015

I’m sure they did.  It could also have been any number of other things.  I’m just guessing.  It could have been someone trying to scan their enterprise too and went a bit rogue.

Not everyone reads NANOG believe it or not :)

Either way, if you haven’t upgraded for a 9 month old security advisory, shame on you.  I don’t care what your change management process looks like, it’s bordering on network malpractice IMHO.

- Jared

> On Jul 9, 2015, at 10:09 AM, Colin Johnston <colinj at gt86car.org.uk> wrote:
> 
> you would think a researcher would stop once he realised effect being caused ?
> 
> Colin
> 
>> On 9 Jul 2015, at 14:08, Jared Mauch <jared at puck.nether.net> wrote:
>> 
>> My guess is a researcher. 
>> 
>> We saw the same issue in the past with a Cisco microcode bug and people doing ping record route. When it went across a LC with a very specific set of software it would crash. 
>> 
>> If you crashed just upgrade your code, don't hide behind blocking an IP as people now know what to send/do. It won't be long. 
>> 
>> Jared Mauch
>> 
>>> On Jul 9, 2015, at 7:44 AM, Colin Johnston <colinj at gt86car.org.uk> wrote:
>>> 
>>> Hi Jared,
>>> thanks for update
>>> 
>>> do you know provider/source ip of the source of the attack ?
>>> 
>>> Colin
>>> 
>>>> On 9 Jul 2015, at 12:27, Jared Mauch <jared at puck.nether.net> wrote:
>>>> 
>>>> Really just people not patching their software after warnings more than six months ago:
>>>> 
>>>> July-08 UPDATE: Cisco PSIRT is aware of disruption to some Cisco customers with Cisco ASA devices affected by CVE-2014-3383, the Cisco ASA VPN Denial of Service Vulnerability that was disclosed in this Security Advisory. Traffic causing the disruption was isolated to a specific source IPv4 address. Cisco has engaged the provider and owner of that device and determined that the traffic was sent with no malicious intent. Cisco strongly recommends that customers upgrade to a fixed Cisco ASA software release to remediate this issue. 
>>>> 
>>>> Cisco has released free software updates that address these vulnerabilities. Workarounds that mitigate some of these vulnerabilities are available.
>>>> 
>>>> Jared Mauch
>>>> 
>>>>> On Jul 8, 2015, at 1:15 PM, Michel Luczak <frnog at shrd.fr> wrote:
>>>>> 
>>>>> 
>>>>>> On 08 Jul 2015, at 18:58, Mark Mayfield <Mark.Mayfield at cityofroseville.com> wrote:
>>>>>> 
>>>>>> Come in this morning to find one failover pair of ASA's had the primary crash and failover, then a couple hours later, the secondary crash and failover, back to the primary.
>>>>> 
>>>>> Not sure it’s related but I’ve read reports on FRNoG of ASAs crashing as well, seems related to a late leap second related issue.
>>>>> 
>>>>> Regards, Michel