This Week In Security: Intel Atoms Spill Secrets, ICMP Poisons DNS, And The Blacksmith

Intel has announced CVE-2021-0146, a vulnerability in certain processors based on the Atom architecture, and the Trusted Platform Module (TPM) is at the center of the problem. The goal of the system around the TPM is to maintain system integrity even in the case of physical access by an attacker, so the hard drive is encrypted using a key stored in a secure chip on the motherboard. The TPM chip holds this encryption key and provides it during the boot process. When combined with secure boot, this is a surprisingly effective way to prevent tampering or data access even in the case of physical access. It’s effective, at least, when nothing goes wrong.

Earlier this year, we covered a story where the encryption key could be sniffed directly from the motherboard, by tapping the traces connecting the TPM to the CPU. It was pointed out that TPM 2.0 can encrypt the disk encryption key on the traces, making this attack impossible.

The entire Trusted Compute Model is based on the premise that the CPU itself is trustworthy. This brings us back to Intel’s announcement that a debug mode could be enabled via physical access. In this debug mode, the CPU master key can be extracted, leading to complete compromise. The drive encryption key can be recovered, and unsigned firmware can be loaded to the Management Engine. This means data in the TPM enclave and the TPM-stored encryption key can be compromised. Updated firmware is rolling out through motherboard vendors to address the problem. Continue reading “This Week In Security: Intel Atoms Spill Secrets, ICMP Poisons DNS, And The Blacksmith”

Apple Finally Fixes DNS Bug

With today’s release of Security Update 2008-006 Apple has finally addressed this summer’s DNS bug. In their previous update they fixed BIND, but that only affects people running servers. Now, they’ve updated mDNSResponder. Clients are no longer susceptible to DNS cache poisoning attacks thanks to the inclusion of source port randomization.

The Security Update addresses some other interesting bugs. Time Machine was saving sensitive logs without using the proper permissions, so any user could view them.

[photo: edans]

Black Hat 2008: Dan Kaminsky Releases DNS Information

[Dan Kaminsky]’s much anticipated talk on his DNS findings finally happened at Black Hat 2008 in Las Vegas today. [Dan] has already uploaded the complete slides from his talk as well as posted a short summary to his site. New information in the slides since our previous coverage includes “Forgot My Password” attacks and new attacks on internal network vulnerabilities as a side of effect of DNS cache poisoning. [Dan]’s talk today was over capacity; our shot of the conference room overflow is shown above.