Loïc Duflot

Loïc Duflot is a French computer security researcher whose work, carried out while employed at France's Direction Centrale de la Sécurité des Systèmes d'Information (DCSSI) and later its successor agency ANSSI, focused on a then-underexplored area of offensive security: showing that x86 processor and PC chipset features, used exactly as documented, could be leveraged to defeat operating-system and hypervisor security models without relying on any implementation bug.

His best-known result was presented in March 2006 at the CanSecWest conference in Vancouver, in a talk co-authored with Daniel Etiemble and Olivier Grumelard titled 'Security Issues Related to Pentium System Management Mode.' The team demonstrated that System Management Mode (SMM) — a highly privileged x86 execution mode originally intended for firmware-level tasks such as power management — could be entered by an attacker with sufficient initial privileges to escalate to full control of the machine, including a proof-of-concept 'root to kernel' privilege escalation on OpenBSD running in its hardened 'Highly Secure' securelevel mode, and a related exploit against NetBSD. The underlying issue was that on most tested motherboards the chipset's SMRAM lock bit (D_LCK) was not actually set, leaving the memory region backing SMM unprotected from tampering by a sufficiently privileged local process. Following the presentation, Intel reportedly opened a consultation with BIOS vendors to get the lock bit set correctly. The same research was also presented in French at SSTIC 2006 (1 June 2006, with Etiemble and Grumelard) and published in MISC magazine issue 26.

Duflot continued this line of work throughout a doctoral thesis, 'Contribution à la sécurité des systèmes d'exploitation et des microprocesseurs,' publicly defended on 18 October 2007 at Université Paris-Sud (Paris XI) under Daniel Etiemble, with a jury that included Jacques Stern as president. The thesis extended the SMM attacks to x86-64 architectures and examined further hardware/software security inconsistencies. In 2007 he presented, with Laurent Absil at PacSec, work showing that chipset I/O mechanisms — the AGP graphics aperture and UHCI-compliant USB host controllers — could be used from application level to break the isolation provided by Intel VT-x virtualization, again without exploiting any coding flaw.

He kept returning to SMM and firmware trust issues in subsequent years: a 2008 ESORICS paper (later expanded in the Journal of Computer Virology) surveyed CPU bugs and backdoors and their security consequences; at CanSecWest 2009, with Olivier Levillain, Benjamin Morin and Olivier Grumelard, he presented 'Getting into the SMRAM: SMM Reloaded,' showing that even when the SMRAM lock bit was correctly set, cache-poisoning techniques could still allow an attacker to write to SMRAM. Work on ACPI and SMI (System Management Interrupt) handlers as further routes to undermine 'trusted computing' assumptions followed at TRUST 2009 and in the Journal of Computer Virology (2010), and was also explored in a book chapter, 'On the Limits of Hypervisor- and Virtual Machine Monitor-Based Isolation' (Towards Hardware-Intrinsic Security, 2010).

By 2011, with DCSSI having been folded into the newly created Agence nationale de la sécurité des systèmes d'information (ANSSI) on 7 July 2009, Duflot's affiliation on subsequent publications shifted accordingly. That year, with Yves-Alexis Perez and Benjamin Morin, he published 'What If You Can't Trust Your Network Card?' at RAID 2011, demonstrating that a vulnerability in a network adapter's ASF remote-administration firmware feature could be used to plant a DMA-based backdoor in the OS kernel, opening a reverse shell on a crafted ICMP packet; a related CanSecWest 2011 talk, 'Run-time firmware integrity verification,' discussed countermeasures such as IOMMU-based protections. No further publicly documented publications or talks by Duflot have been verified beyond this period in the sources consulted for this article, and no independent biographical page (e.g., a dedicated Wikipedia entry) was found to exist for him.

Timeline

• 2006-03Presents 'Security Issues Related to Pentium System Management Mode' at CanSecWest (Core06), with Daniel Etiemble and Olivier Grumelard, demonstrating SMM-based privilege escalation on OpenBSD and NetBSD.
• 2006-06-01Presents the French-language version of the SMM research at SSTIC 2006, co-authored with Daniel Etiemble and Olivier Grumelard.
• 2006Publishes 'Sécurité logicielle et fonctionnalités matérielles: quelle cohérence?' in MISC magazine, issue 26, with Etiemble and Grumelard.
• 2007Presents 'Programmed I/O accesses: a threat to Virtual Machine Monitors?' at PacSec, with Laurent Absil, on bypassing Intel VT-x isolation via AGP and USB chipset features.
• 2007-10-18Publicly defends his PhD thesis, 'Contribution à la sécurité des systèmes d'exploitation et des microprocesseurs,' at Université Paris-Sud (Paris XI).
• 2008Publishes 'CPU Bugs, CPU Backdoors and Consequences on Security' at ESORICS 2008.
• 2009-07-07DCSSI, Duflot's employer, is reorganized into the new Agence nationale de la sécurité des systèmes d'information (ANSSI).
• 2009-03Presents 'Getting into the SMRAM: SMM Reloaded' at CanSecWest, with Olivier Levillain, Benjamin Morin and Olivier Grumelard, defeating the SMRAM lock-bit protection via cache poisoning.
• 2009Publishes 'ACPI: Design Principles and Concerns' at TRUST 2009 (also presented at SSTIC 2009), with Olivier Levillain and Benjamin Morin.
• 2010Publishes 'ACPI and SMI handlers: some limits to trusted computing' in the Journal of Computer Virology, and 'On the Limits of Hypervisor- and Virtual Machine Monitor-Based Isolation' as a book chapter in Towards Hardware-Intrinsic Security.
• 2011Publishes 'What If You Can't Trust Your Network Card?' at RAID 2011 with Yves-Alexis Perez and Benjamin Morin, and presents related 'Run-time firmware integrity verification' work at CanSecWest, by this point credited to ANSSI/SGDSN.