Tag Archives: Transparent Data Encryption

Plundervolt. Don’t panic!

16 December 2019

Last Tuesday, Intel (1) published a patch for a new hardware vulnerability dubbed Plundervolt (CVE-2019-11157). As always with hardware vulnerabilities, Plundervolt got a lot of attention in the media.(2)(3)(4) A Google search for “plundervolt intel” shows about 167.000 hits as of today. The vulnerability was detected by a research team lead by Kit Murdock (5) some month ago.

In parallel, Microsoft published a patch for the privilege escalation vulnerability CVE-2019-1458.(6) CVE-2019-1458 is actively used in attacks (7), so it also got some media attention (Google search “CVE-2019-1458”: 88.000 hits as of today).

Plundervolt logo.

Plundervolt logo.

From my point of view, hardware vulnerabilities are always somewhat overvalued, especially in terms of their benefit in cyber operations. The vulnerabilities named RyzenFall, FallOut, Chimera and MasterKey in AMD processors, which were discovered last year, are maybe the best examples.(8) So, lets take a closer look on PlunderVolt and CVE-2019-1458.

The table below shows the CVSS V3.1 Severity for the vulnerabilities.

Plundervolt CVE-2019-1458 comparison

Plundervolt / CVE-2019-1458 comparison

The main difference is in the Privileges Required (PR) to exploit the vulnerability. For Plundervolt, Murdock et al. “assume the standard Intel SGX adversary model where the attacker has full control over all software running outside the enclave (including privileged system software such as operating system and BIOS).”(5) That means that the system must already be fully compromised before Plundervolt can be exploited.

In contrast, CVE-2019-1458 allows the attacker to acquire high privileges on a system once he hijacked a standard user account. So, by exploiting CVE-2019-1458 the attacker sets up the environment to exploit Plundervolt.

From an attacker’s point of view, CVE-2019-1458 is more valuable than Plundervolt. Once one system is compromised, the attacker can use it as base of operations for the exploration of the victim’s network. In the worst case, the Active Directory is compromised within some minutes, so the attacker has access to all secrets, or he can push ransomware to all computers.

For organized crime and APTs, CVE-2019-1458 is a universally exploitable tool to achieve goals.

Plundervolt gets interesting if the attacker is interested in encryption key details which are used internally only, for example in Transparent Database Encryption (TDE) or in trusted execution environments. Murdock et al. “demonstrate the effectiveness of our attacks by injecting faults into Intel’s RSA-CRT and AES-NI implementations running in an SGX enclave, and we reconstruct full cryptographic keys with negligible computational efforts.”(5) In the worst case, this results in the loss of all data in a TDE secured database, since vendors use Intel’s AES-NI on-chip implementation to speed up cryptographic computations.

So, Plundervolt is interesting for organized crime and APTs when it comes to industrial espionage or in attacks against targets which are relevant for national security.

Fortunately, the time frame for exploitation is short. The patch for CVE-2019-1458 will be automatically rolled out through the WSUS infrastructure within the next weeks. Plundervolt should be patched, with high priority on critical systems, if a company is target of espionage or operates critical infrastructures.

Do you know your threat profile and critical systems? Without this knowledge efficient vulnerability management is not possible. Not sure? So, take it as a New Year’s resolution…

References

  1. Intel Security Center. INTEL-SA-00289 [Internet]. Intel Security Center. 2019 [cited 2019 Dec 13]. Available from: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00289.html
  2. Gatlan S. Intel Patches Plundervolt, High Severity Issues in Platform Update [Internet]. BleepingComputer. 2019 [cited 2019 Dec 13]. Available from: https://www.bleepingcomputer.com/news/security/intel-patches-plundervolt-high-severity-issues-in-platform-update/
  3. O’Donnell L. Modern Intel CPUs Plagued By Plundervolt Attack | Threatpost [Internet]. threatpost. 2019 [cited 2019 Dec 13]. Available from: https://threatpost.com/intel-cpus-plundervolt-attack/151006/
  4. Khandelwal S. New PlunderVolt Attack Targets Intel SGX Enclaves by Tweaking CPU Voltage [Internet]. The Hacker News. 2019 [cited 2019 Dec 13]. Available from: https://thehackernews.com/2019/12/intel-sgx-voltage-attack.html
  5. Murdock K, Oswald D, Garcia FD, Van Bulck J, Gruss D, Piessens F. Plundervolt: Software-based Fault Injection Attacks against Intel SGX}. In: Proceedings of the 41st IEEE Symposium on Security and Privacy (S&P’20) [Internet]. San Francisco, CA; 2019 [cited 2019 Dec 13]. Available from: https://plundervolt.com/
  6. MSRC. CVE-2019-1458 | Win32k Elevation of Privilege Vulnerability [Internet]. Microsoft Security. 2019 [cited 2019 Dec 16]. Available from: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1458
  7. Kaspersky Global Research and Analysis Team. Windows 0-day exploit CVE-2019-1458 used in Operation WizardOpium | Securelist [Internet]. SECURELIST. 2019 [cited 2019 Dec 16]. Available from: https://securelist.com/windows-0-day-exploit-cve-2019-1458-used-in-operation-wizardopium/95432/
  8. Cimpanu C. AMD Confirms RyzenFall, MasterKey, Fallout, and Chimera Vulnerabilities [Internet]. BleepingComputer. 2018 [cited 2019 Dec 16]. Available from: https://www.bleepingcomputer.com/news/hardware/amd-confirms-ryzenfall-masterkey-fallout-and-chimera-vulnerabilities/

Windows 2008 Server End of Life: The best chance to move to the cloud

30 June 2018

Windows 2008 Server End of Life is near. Within the next months many companies are busy with the replacement of Windows 2008 based infrastructure and application servers to avoid the next Wannacry or NotPetya.

It appears to me that this is the best opportunity to migrate at least application servers to the cloud. And, in the best case, to get rid of the servers at all by transforming the application to SAAS. If technical or the organizational limitations do not allow this at least the transformation to PAAS and IAAS should be considered.

What stops us from doing this? Very often it is the fear of loss of access to critical business data or the fear of loss of the data at all. At least in the latter case technical protection measures can be applied to mitigate this issue.

Transparent database encryption

Transparent database encryption (TDE) is often the matter of choice. All encryption is performed transparently by the database service, with no impact on the application and the users because only the database files or critical attributes in tables are encrypted. User interaction is required only during database startup to activate the encryption engine.

Unfortunately, TDE provides only encryption at rest. Thus TDE stops infrastructure admins from using unauthorized copies of a database or a virtual database server because they cannot activate the encryption engine. Once the database is started all users and database administrators have access.

Application level encryption

With Application level encryption (ALE) all encryption is performed by the application. Data is encrypted when entered in or retrieved through the application. Thus data is encrypted during transfer and at rest.

As long as the access is not routed through the application server the data are accessible for no one. Even infrastructure or database admins are barred unless they have access to the encryption key.

The security problem is shifted towards that of operational security of the application server. A solution to this problem could be to encrypt the data in the database with a key that is encrypted against the users access keys. This ensures that the encrypted data cannot be decrypted without access to at least one users key.

The remaining risk is that an attacker reads the keys or the plain text data from the process memory of the application service.

The effort to implement application level encryption is high because the application has to be changed. In addition, a key infrastructure must be set up to avoid data loss in the case a user key is e.g. inaccessible. But the gain in information and operational security is high.

The pros and cons of the encryption concepts in summary.

Table 1: Database Encryption Concepts Summary

Table 1: Database Encryption Concepts Summary

With Application Level Encryption, outsourcing or cloud adoption is made easy.

Have a good weekend.

Premera hacked – 11 million financial and medical records stolen

19 March 2014

When news about the Premera hack showed up in my mailbox this afternoon I was really amazed. The second time for this year a health insurance company was hit.

On skim reading the news about the Premera attack I wondered, when the magic word encryption would appear the first time. Finally I found this statement in Warwick Ashford’s post ‘Premera hack exposes 11 million financial and medical records’. Richard Blech, chief executive of security firm Secure Channels, said:

“With advanced and unhackable encryption, the hacker is left with a bunch of useless bits and bytes.”

Richard Blech talks about encryption at the application level. Application level encryption is not as useless as database level transparent encryption in the defense against attackers.

But even application level encryption is almost useless in the case of malicious insiders because, apart from the fact that they use stolen login data, they sign in to the company just like a normal employee. Therefore they are able to access even data which are encrypted on the application level, because they are authorized to do this.

In my opinion, to use advanced encryption as the core process of a protection strategy is as irresponsible as to use no encryption at all. Strict Identity and Access Management, combined with Two Factor Authorization for all employees, and regular security trainings create the first and second line of defense. Encryption is the last line of defense.

Take care!

Anthem Hacked – The call for ‘More of Everything’ grows louder

19 February 2015

Just some thoughts about the call for more technology, encryption, pen testing, etc.

The big question is: Would database encryption have slowed down or stopped the attackers? From my experience with Transparent Data Encryption (TDE) in the Oracle universe I can only answer: Definitely Not!

If it’s properly set up TDE works very well to prevent unauthorized access to data in rest. Administrators and users are not able to read or copy database files when e.g. the database is shut down.

But as long as the database is started TDE works transparent for all users and the administrators: They can access the data with applications or SQL tools without any restriction.

If you like to keep the administrators away from the data you must set up Oracle Database Vault on top of TDE. Database Vault acts as a firewall between the users and the administrators. Administrators can run their administrative tasks, but they could no longer access the data. In addition, the Separation of Duties principle is enforced for security critical operations like definition of users.

But what’s about malicious insiders? Malicious insiders are responsible for about two-third of all attacks, but neither TDE nor Vault would stop them from accessing all data. With Label Security a fine-grain access control system is available that gives data admins the opportunity to restrict a user to individual data sets in a table.

Sounds like rocket science, doesn’t it? Far from it. Most of this products are for several years in the market, but they are widely unknown, and, the effort for implementation is high.

That’s it for today.

For further reading please see

Anthem Cyber Hack: 5 Fast Facts You Need to Know

Anthem Breach Should Convince Healthcare To Double Down On Security

Anthem Breach Prompts New York To Conduct Cybersecurity Reviews Of All Insurers