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As most of you have read, there’s another SSL exploit out there. As announced by OpenSSL.org (https://www.openssl.org/~bodo/ssl-poodle.pdf), the Poodle attack has been designed to take advantage of a vulnerability in the SSL V 3.0 protocol using the CBC mode encryption. Though a few other vulnerabilities were disclosed (https://www.openssl.org/news/secadv_20141015.txt), the Poodle attack seems to have gained much more attention. To be more specific about the vulnerability, the attack exploits the vulnerability found in the implementation of the CBC mode in SSL V 3.0 where in the padding bytes are not checked against any value nor covered by the message digest (MAC). The attack itself is complicated to carry out as it involves a client downgrade dance along with the attacker being the man-in-middle and having the ability to control/modify the traffic from the client to a server. Though the attack involves intricacy in execution, it is easy to carry out given today’s computing resources.
By carefully crafting and sending a huge number of requests to a server, an attacker can extract various parts of a HTTP communication. This could be the Cookie key-values or Authentication headers etc. After extracting the intended parts, the attacker can later infiltrate and cause data leakage.
Netskope continuously monitor thousands of SaaS apps and our preliminary analysis has shown that more than 3,562 (as of October 15, 2014 — see below for an updated count) of them are still vulnerable due to their current support SSL V 3.0. We will provide an update of this count daily and we’re reaching out to vendors to counsel them on this vulnerability. We’re recommending that they turn-off the support for SSL V 3.0 and to watch for anomalous behaviors on any other network protection devices (e.g., IPS), such as using SSL V 3.0 flows with CBC mode and huge number of connection failures or web server error messages in a very short period of time.
For our customers the good news is that Netskope Active™ is configured to never fallback to SSL 3.0 protocol. This ensures that traffic going through the Netskope Active Platform is secure and is not susceptible to the Poodle attack. For example, say “Acme SaaS App” has this vulnerability — by using Netskope Active™ we ensure that no hacker with a malicious intent can take control of the session from end users to “Acme SaaS App.”
For consumers, it is our recommendation that you turn-off/disable the use of SSL V 3.0 in client programs such as browsers.
For more details of how the Poodle attack works and some background, check out our video below. If you’d like to get a little deeper into this subject or discuss proactive steps for getting ahead of threats like this, please don’t hesitate to email us at [email protected].
*** OCTOBER 16 UPDATE *** 3,329 cloud apps remain vulnerable, this is down from yesterday’s count of 3,562
*** OCTOBER 17 UPDATE *** 2,754 cloud apps remain vulnerable
*** OCTOBER 18 UPDATE *** 1,862 cloud apps remain vulnerable
*** OCTOBER 19 UPDATE *** 1,737 cloud apps remain vulnerable
*** OCTOBER 20 UPDATE *** 1,677 cloud apps remain vulnerable
*** OCTOBER 21 UPDATE *** 1,632 cloud apps remain vulnerable
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