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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