TLS re-negotiation attack on SIP/TLS of FreeSWITCH?
Hi all, i read about the TLS-RENEGOTIATION vulnerability: http://www.educatedguesswork.org/2009/11/understanding_the_tls_renegoti.html http://www.sslshopper.com/article-ssl-and-tls-renegotiation-vulnerability-di... www.phonefactor.com/sslgapdocs/Renegotiating_TLS.pdf Does the FreeSWITCH SIP/TLS implementation suffer from the TLS Renegotiation vulnerability or the TLS-renegotiation it's disabled by default, in how OpenSSL is used? Fabio Pietrosanti
I'm not 100% sure how its handled because its done down in the Sofia library. I'm not too sure we are very vulnerable to this... I can't think of one thing in a sip call via TLS this could actually cause a problem with. Its not the same ball game when its your browser vs a sip phone where most don't even check the cert is valid in the first place. /b On Sep 22, 2010, at 9:23 AM, Fabio Pietrosanti (naif) wrote:
Hi all,
i read about the TLS-RENEGOTIATION vulnerability:
http://www.educatedguesswork.org/2009/11/understanding_the_tls_renegoti.html http://www.sslshopper.com/article-ssl-and-tls-renegotiation-vulnerability-di... www.phonefactor.com/sslgapdocs/Renegotiating_TLS.pdf
Does the FreeSWITCH SIP/TLS implementation suffer from the TLS Renegotiation vulnerability or the TLS-renegotiation it's disabled by default, in how OpenSSL is used?
Fabio Pietrosanti
There is a nice thread related to Apache ad OpenSSL plenty of nice tech information on how it's fixed in Apache starting from a certain OpenSSL version: http://www.mail-archive.com/dev@httpd.apache.org/msg46216.html Additionally there was a very quick OpenSSL fix when in 2009 the vulnerability was discovered: http://www.links.org/files/no-renegotiation-2.patch They could be good hint to have a look and be sure that TLS just does not do TLS re-negotiation (the fix it's to just disable TLS re-negotiation). Ah! Regarding the certificate check: - With SNOM Firmware 8 and with PrivateGSM Enterprise (i will release early october for Nokia/iPhone/Blackberry on http://www.privatewave.com) there's a forced server-side certificate check to enforce the SIP/TLS security checking. However the TLS re-negotiation issue it's a different story. Fabio On 22/09/10 16.33, Brian West wrote:
I'm not 100% sure how its handled because its done down in the Sofia library. I'm not too sure we are very vulnerable to this... I can't think of one thing in a sip call via TLS this could actually cause a problem with. Its not the same ball game when its your browser vs a sip phone where most don't even check the cert is valid in the first place.
/b
On Sep 22, 2010, at 9:23 AM, Fabio Pietrosanti (naif) wrote:
Hi all,
i read about the TLS-RENEGOTIATION vulnerability:
http://www.educatedguesswork.org/2009/11/understanding_the_tls_renegoti.html http://www.sslshopper.com/article-ssl-and-tls-renegotiation-vulnerability-di... www.phonefactor.com/sslgapdocs/Renegotiating_TLS.pdf
Does the FreeSWITCH SIP/TLS implementation suffer from the TLS Renegotiation vulnerability or the TLS-renegotiation it's disabled by default, in how OpenSSL is used?
Fabio Pietrosanti
_______________________________________________ FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
Please direct your question to the sofia-users list also. /b On Sep 22, 2010, at 9:45 AM, Fabio Pietrosanti (naif) wrote:
There is a nice thread related to Apache ad OpenSSL plenty of nice tech information on how it's fixed in Apache starting from a certain OpenSSL version: http://www.mail-archive.com/dev@httpd.apache.org/msg46216.html
Additionally there was a very quick OpenSSL fix when in 2009 the vulnerability was discovered: http://www.links.org/files/no-renegotiation-2.patch
They could be good hint to have a look and be sure that TLS just does not do TLS re-negotiation (the fix it's to just disable TLS re-negotiation).
Ah! Regarding the certificate check: - With SNOM Firmware 8 and with PrivateGSM Enterprise (i will release early october for Nokia/iPhone/Blackberry on http://www.privatewave.com) there's a forced server-side certificate check to enforce the SIP/TLS security checking.
However the TLS re-negotiation issue it's a different story.
Fabio
We do set TPTAG_TLS_VERIFY_POLICY(0) on our TLS sofia profiles. /b On Sep 22, 2010, at 9:45 AM, Fabio Pietrosanti (naif) wrote:
There is a nice thread related to Apache ad OpenSSL plenty of nice tech information on how it's fixed in Apache starting from a certain OpenSSL version: http://www.mail-archive.com/dev@httpd.apache.org/msg46216.html
Additionally there was a very quick OpenSSL fix when in 2009 the vulnerability was discovered: http://www.links.org/files/no-renegotiation-2.patch
They could be good hint to have a look and be sure that TLS just does not do TLS re-negotiation (the fix it's to just disable TLS re-negotiation).
Ah! Regarding the certificate check: - With SNOM Firmware 8 and with PrivateGSM Enterprise (i will release early october for Nokia/iPhone/Blackberry on http://www.privatewave.com) there's a forced server-side certificate check to enforce the SIP/TLS security checking.
However the TLS re-negotiation issue it's a different story.
Fabio
participants (2)
-
Brian West
-
Fabio Pietrosanti (naif)