Hi again

These brackets are for emphasis, sorry for not to clarify this, but it
clearly looks like it is a regexp issue, I´m going to deal with it now
and I´ll post if I´m able to solve it. May be some other people are
dealing with this, any help would really appreciated. It is a ticket
opened on github as suggested? I´ll do that in such case

Kind Regards

2015-02-10 13:31 GMT+01:00 dan (ddp) <[email protected]>:
> On Mon, Feb 9, 2015 at 4:23 PM, Daniel Calvo Castro
> <[email protected]> wrote:
>> Just today I´ve been experiencing same issues trying to get OSSIM + OSSEC
>> working with an asterisk box, I´ve followed this link [1], and trying to
>> enumerate users I´m able to correlate and fire mails correctly with OSSIM,
>> but UI always show $SRCIP 0.0.0.0 so seems useless to configure post-actions
>> like DROP $SRCIP.
>>
>> Taking a look at the link provided, his log appears only to contain src IP,
>> like that:
>>
>> May 19 11:42:17 asterisk asterisk[5200]: NOTICE[14808]: chan_sip.c:15889 in
>> handle_request_register: Registration from ‘”355″<sip:[email protected]>’
>> failed for ‘[[[192.168.210.48]]]’ – No matching peer found
>>
>> You can see "failed for 'x.x.x.x' only
>>
>> But seems like in recent versions like me ( stable Elastix  and ossec 2.8 ),
>> log says "failed for 'x.x.x.x:UDPPORT'  so I figured it could be some regexp
>> issue, time to check.
>>
>> - log from post provided and default regexp in decoder.xml "\d+.\d+.\d+.\d+"
>> in regexpr.com correctly matches SRCIP but it fails, you can try yourself:
>>
>> May [[[[[[19 11:42:17]]]]] asterisk asterisk[5200]: NOTICE[14808]:
>> chan_sip.c:15889 in handle_request_register: Registration from
>> ‘”355″<sip:[[[[email protected]]]]]]>’ failed for ‘192.168.210.48’ – No
>> matching peer found
>>
>
> Are these brackets really in the log message, or are they there for emphasis?
>
>> - Escaping dot characters solves the problem, \d+\.\d+\.\d+\.\d+ correctly
>
> \. matches any single character.
>
>> matches IP address, and for IP:UDPPORT you can use \d+\.\d+\.\d+\.\d+\:\d+.
>>
>> But placing all this tweakings in decoder and restarting ossec server did
>> not work, OSSIM always matches SRCIP like 0.0.0.0. In fact, I modified this
>> ossec as is the event seen in OSSIM UI when I run svwar:
>>
>
> For some reason I can't get the regex to work with the single quotes
> around the IP address.
>
>> <rule id="6212" level="5">
>> <if_sid>6201</if_sid>
>> <match>No matching peer found</match>
>> <description>Login session failed (invalid extension).</description>
>> <group>invalid_login,</group>
>> </rule>
>>
>>
>> I´ll keep trying tomorrow, keep in touch please!
>>
>> Kind Regards,
>>
>> Daniel
>>
>> [1] https://sysbrain.wordpress.com/2010/05/24/asterisk-ossec-part-ii/
>>
>> 2015-02-09 20:21 GMT+01:00 dan (ddp) <[email protected]>:
>>>
>>> On Mon, Feb 9, 2015 at 2:10 PM, Security <[email protected]>
>>> wrote:
>>> > Could be.
>>> > I don't know if I have to write to the dev mailing list to have it fixed
>>> > in
>>> > the next release.
>>> > I'm running my modified version on 3 asterisk instances and I'm very
>>> > happy
>>> > with the results.
>>> >
>>>
>>> Your best option is to open an issue on the github.
>>> https://github.com/ossec/ossec-hids
>>> If I remember I'll try to come up with a rule that covers both the old
>>> and new log samples we have.
>>>
>>> > Regards,
>>> >
>>> > Simon Gillet
>>> >
>>> > Le 9 févr. 2015 à 14:08, dan (ddp) <[email protected]> a écrit :
>>> >
>>> > On Sun, Feb 8, 2015 at 5:26 PM, Security <[email protected]>
>>> > wrote:
>>> >
>>> > Hello,
>>> >
>>> > I think the Asterisk rules could be wrong. Or at least for Ubuntu.
>>> > OSSEC always failed blocking brute force attempt on Asterisk.
>>> > A standart log entry for brute force attempt looks like:
>>> >
>>> > Dec 17 22:37:25 new asterisk[20110]: NOTICE[20127]: chan_sip.c:25030 in
>>> > handle_request_register: Registration from '"6100" <sip:[email protected]>'
>>> > failed for '85.25.110.243:5188' - Wrong password
>>> >
>>> >
>>> > This log sample is different than the one we were provided previously.
>>> >
>>> > I changed the rules in the decoder.xml files and I have no much better
>>> > results.
>>> >
>>> > Let me know if I'm wrong, I'm not a OSSEC expert but now I block the
>>> > brute
>>> > force attempts.
>>> >
>>> > Regards,
>>> >
>>> > Simon Gillet
>>> >
>>> > I changed this rule:
>>> >
>>> > <decoder name="asterisk-denied">
>>> >  <parent>asterisk</parent>
>>> >  <prematch>^NOTICE[\d+]: \S+ in \S+: Registration from </prematch>
>>> >  <regex offset="after_prematch">^\S+ failed for
>>> > '(\d+.\d+.\d+.\d+)'</regex>
>>> >  <order>srcip</order>
>>> > </decoder>
>>> >
>>> > To this one:
>>> >
>>> > <decoder name="asterisk-denied">
>>> >  <parent>asterisk</parent>
>>> >  <prematch>^NOTICE[\d+]: \S+ in \S+: Registration from \S+
>>> > \S+</prematch>
>>> >  <regex offset="after_prematch">^failed for '(\S+):(\d+)'</regex>
>>> >  <order>srcip,srcport</order>
>>> > </decoder>
>>> >
>>> > And this rule:
>>> >
>>> > <decoder name="asterisk-denied2">
>>> >  <parent>asterisk</parent>
>>> >  <prematch>Registration from </prematch>
>>> >  <regex offset="after_prematch">failed for '(\d+.\d+.\d+.\d+)'</regex>
>>> >  <order>srcip</order>
>>> > </decoder>
>>> >
>>> > To this one:
>>> >
>>> > <decoder name="asterisk-denied2">
>>> >  <parent>asterisk</parent>
>>> >  <prematch>Registration from </prematch>
>>> >  <regex offset="after_prematch">failed for '(\S+):(\d+)'</regex>
>>> >  <order>srcip,srcport</order>
>>> > </decoder>
>>> >
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