SSLv3 POODLE Vulnerability Official Release
Finally we got an official announcement. For all the details, jump straight to the original announcement [1]. Below see the TL;DR; version:
The problem is limited to SSLv3. SSLv3 is often considered similar to TLSv1.0, but the two protocols are different.
SSLv3 had issues in the past. Remember the BEAST attack? It was never resolved (other then moving to TLS 1.1/2). The only alternative was to use a stream cipher like RC4, which had its own problems.
But this POODLE issue is different. With block ciphers, we have a second problem: What if the block to be encrypted is too short? In this case, padding is used to make up for the missing data. Since the padding isn't really considered part of the message, it is not covered by the MAC (message authorization code) that verified message integrity.
So what does this mean in real live? The impact is similar to the BEAST attack. An attacker may either play MitM, or may be able to decrypt parts of a message if the attacker is able to inject data into the connection just like in the BEAST attack. The attack allows one to decrypt one byte at a time, if the attacker is able to inject messages right after that byte that include only padding.
What should you do: Disable SSLv3. There is no patch for this. SSLv3 has reached the end of its useful life and should be retired.
This isn't a "patch now". Give it some time, test it carefully, but get going with it. The other problem is that this is a client and a server issue. You need to disable SSLv3 on either. Start with the servers for highest impact, but then see what you can do about clients.
The other option to "fix" this problem is to use SSL implementations that take advantage of the TLS_FALLBACK_SCSV feature. This feature notifies the other side that you first tried the stronger cipher. This way, they can reject the downgrade attempt that may have been introduced by a MitM attack. But it isn't clear which implementations use this feature at this point, and which don't. A patch for OpenSSL 1.0.1 was released earlier today implementing TLS_FALLBACK_SCSV
FAQ
To test if your server is vulnerable: Use https://ssltest.com
To test if your client is vulnerable: We setup a test page at https://www.poodletest.com . If you can connect, then your client supports SSLv3 .
So far, we tested :
| Firefox 32 | IE 11 | Safari 7.1 | Chrome 37 | Opera | |
| Windows 7 | ok | vuln | vuln | vuln | |
| OS X 10.9.5 | ok | N/A | vuln | vuln | |
| iOS 8.0.2 | vuln | N/A | vuln | vuln | vuln |
To turn off SSLv3 support in Internet Explorer 11:
Setting -> Internet Options -> Advanced Tab -> Uncheck "SSLv3" under "Security".
[1] https://www.openssl.org/~bodo/ssl-poodle.pdf
OpenSSL Vulnerability leaked via OpenBSD patch (NOT!)?
Yesterday, a number of news sites published speculative reports about a possible OpenSSL bug to be fixed today. According to these reports, the bug affects SSL 3, and is "critical". Can't wait for the official announcement to see what is actually happening here ;-)
Initially, it looked like an OpenBSD patch lead to an answer, but turns out the patch was old (thx to those who wrote in and responded, in particular based on the tweet by @martijn_grooten ). But instead, there are new leads now, in particular a discussion on Stackexchange [1]. In this discussion, a comment by Thomas Pornin outlines how padding in SSLv3 can lead to MitM attacks. This would be an outright attack against the SSLv3 protocol, and less against a specific implementation. It would affect clients as well as servers.
We will update this post as we learn more. At this point: Don't panic and wait for a patch from your respective vendor. We are not aware of any active exploitation of this problem, but please let us know if you see any evidence of that happening.
If you choose to disable SSLv3 on a server, but leave TLS 1.0 enabled, Windows XP with IE 6 will no longer be able to connect (but older versions of IE will be able to connect from Windows XP machines).
How can you test if a server supports SSLv3? Either use ssllabs.com, or using the openssl client: (if it connects, it supports SSLv3)
openssl s_client -ssl3 -connect [your web server]:443
How can I check if my browser can live without SSLv3? If you can read this, then you support TLSv1 or higher. I turned off SSLv3 support on this site for now. But pretty much all browsers support SSLv3.
You tell us not to panic, but you turned of SSLv3? Yes. I wanted to see what happens if I turn off SSLv3. So far, the only issue I found was Windows XP with IE 6, a configuration I probably don't want to support anyway.
[1] http://chat.stackexchange.com/transcript/message/18152298#18152298
Microsoft October 2014 Patch Tuesday
Microsoft only published 8 instead of the promised 9 bulletins. Also, of particular interest is MS14-060 which was pre-announced by iSight Partners. iSight has seen this vulnerability exploited in some "APT" style attacks against NATO/US military interests and attributes these attacks to Russia. Attacks like this have happened with many Office vulnerabilities in the past, but it is unusual for a company to announce the respective attacks and CVE numbers ahead of Microsoft's bulletin release. Note that we got a total of 3 already exploited vulnerabilities in this month's release. Don't believe patching fast will protect you. You are probably a few weeks if not months behind at the time the patch is released.
Overview of the October 2014 Microsoft patches and their status.
| # | Affected | Contra Indications - KB | Known Exploits | Microsoft rating(**) | ISC rating(*) | |
|---|---|---|---|---|---|---|
| clients | servers | |||||
| MS14-056 | Cumulative Security Update for Internet Explorer (replaces MS14-052) | |||||
| Microsoft Windows, Internet Explorer CVE-2014-4123, CVE-2014-4124, CVE-2014-4126, CVE-2014-4127, CVE-2014-4128, CVE-2014-4129, CVE-2014-4130, CVE-2014-4132, CVE-2014-4133, CVE-2014-4134, CVE-2014-4137, CVE-2014-4138, CVE-2014-4141, CVE-2014-4123, CVE-2014-4124, CVE-2014-4126, CVE-2014-4127, CVE-2014-4128, CVE-2014-4129, CVE-2014-4130, CVE-2014-4132, CVE-2014-4133, CVE-2014-4134, CVE-2014-4137, CVE-2014-4138, CVE-2014-4140, CVE-2014-4141 |
KB 2987107 |
CVE-2014-4123 has been exploited. |
Severity:Critical Exploitability: 1 |
Critical | Important | |
| MS14-057 | Vulnerabilities in .NET Framework Could Allow Remote Code Execution (replaces MS12-016) | |||||
| Microsoft Windows, Microsoft .NET Framework CVE-2014-4073 CVE-2014-4121 CVE-2014-4122 |
KB 3000414 | No. | Severity:Critical Exploitability: 2 |
Critical | Critical | |
| MS14-058 | Vulnerability in Kernel-Mode Driver Could Allow Remote Code Execution (replaces MS14-015) | |||||
| Microsoft Windows CVE-2014-4113 CVE-2014-4148 |
KB 3000061 | Yes. Used in Limited Attacks | Severity:Critical Exploitability: 0 |
Critical | Critical | |
| MS14-059 | Vulnerability in ASP.NET MVC Could Allow Security Feature Bypass | |||||
| Microsoft Developer Tools CVE-2014-4075 |
KB 2990942 |
Publicly disclosed,not |
Severity:Important Exploitability: 3 |
Less Important | Important | |
| MS14-060 | Vulnerability in Windows OLE Could Allow Remote Code Execution (replaces MS12-005) | |||||
| Microsoft Windows CVE-2014-4114 |
KB 3000869 | yes. against powerpoint. See iSight disclosure. | Severity:Important Exploitability: 0 |
Critical | Important | |
| MS14-061 | Vulnerability in Microsoft Word and Office Web Apps Could Allow Remote Code Execution (MS14-034, MS14-017) | |||||
| Microsoft Office, Microsoft Office Services, Microsoft Office Web Apps CVE-2014-4117 |
KB 3000434 | No. | Severity:Important Exploitability: 1 |
Critical | Important | |
| MS14-062 | Vulnerability in Message Queuing Service Could Allow Elevation of Privilege (MS09-040) | |||||
| Microsoft Windows CVE-2014-4971 |
KB 2993254 | publicly disclosed but not exploited. | Severity:Important Exploitability: 1 |
Important | Important | |
| MS14-063 | Vulnerability in FAT32 Disk Partition Driver Could Allow Elevation of Privilege | |||||
| Microsoft Windows CVE-2014-4115 |
KB 2998579 | No. | Severity:Important Exploitability: 1 |
Important | Important | |
We appreciate updates
US based customers can call Microsoft for free patch related support on 1-866-PCSAFETY
- We use 4 levels:
- PATCH NOW: Typically used where we see immediate danger of exploitation. Typical enviro\ nments will want to deploy these patches ASAP. Workarounds are typically not accepted by users or are not possible. This rating is often used when typical \ deployments make it vulnerable and exploits are being used or easy to obtain or make.
- Critical: Anything that needs little to become "interesting" for the dark side. Best approach is to t\ est and deploy ASAP. Workarounds can give more time to test.
- Important: Things where more testing and other measures can help.
- Less Urt practices for servers such as not using outlook, MSIE, word etc. to do traditional office or lei\ sure work.
- The rating is not a risk analysis as such. It is a rating of importance of the vulnerability and the perceived or even predicted threatatches.
Adobe October 2014 Bulletins for Flash Player and Coldfusion
Adobe published two security bulletins today:
APSB-22 [1] : fixes 3 vulnerabilities in Adobe Flash Player as well as in Adobe Air. The vulnerabilities are rated with a priority of "1" for Flash Player running on Windows and OS X , which means they have already been exploited in targeted attacks.
APSB-23 [2] : another 3 vulnerabilities, but this time in Cold Fusion. The priority for these updates is "2" which indicates that they have not yet been exploited in the wild.
[1] http://helpx.adobe.com/security/products/flash-player/apsb14-22.html
[2] http://helpx.adobe.com/security/products/coldfusion/apsb14-23.html
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