TrueCrypt audit: Probe's nearly all the way in ... no backdoor hit yet

Crypto tool clears code review hurdle

The first phase of crowd-funded audit of TrueCrypt has turned up several vulnerabilities, but nothing particularly amiss and certainly nothing that looks like a backdoor.

iSEC Partners, which was contracted to carry out the audit by the Open Crypto Audit Project (OCAP), ‪found‬ 11 vulnerabilities in the full disk and file encryption software's source code, but no "high-severity" issues. The biggest problems identified were four medium-severity flaws, as detailed in a 32-page report on the audit [PDF].

Code analysis experts carried out fuzzing tests as well as looking at TrueCrypt's Windows kernel driver source code, the application's bootloader and its filesystem driver. iSEC found several weaknesses and common kernel vulnerabilities, but none which contained "immediate exploitation vectors". The security experts found no evidence of backdoors or intentional flaws.

The next phase of the audit will put the cryptographic technology underpinning TrueCrypt under the microscope. The random number generators, cipher suites and algorithms that underpin its encryption will all be given the once-over.

The study was undertaken after OCAP began a grassroots campaign to raise money to answer fundamental questions about the source-available encryption software. The organisation aim was to run a public analysis of the code but it also hopes to resolve TrueCrypt's licence status as well as producing repeatable, deterministic builds of the technology that users can trust.

OCAP's technical advisory board includes the noted cryptographers Bruce Schneier and Moxie Marlinspike. Its directors include Matthew Green, a professor of computer science at Johns Hopkins University, and Kenneth White, a cloud security expert and engineer.

TrueCrypt is a popular utility that encrypts and decrypts entire drives, partitions or files within a virtual disk. The software can also be used to hide volumes of data on discs.

Concerns about TrueCrypt have emerged because of the ongoing controversy about the NSA's work with hardware and software technology vendors on encryption systems and their underlying components. These increased further after of revelations about the agency's efforts to weaken such encryption were leaked by rogue NSA sysadmin Edward Snowden.

A fundraising effort to pay for an independent, professional security audit of TrueCrypt last November raised the necessary funds within days.

More details of TrueCrypt audit project can be found on the IsTrueCryptAuditedYet? website. ®