Renew (Rewriting Newly Executable pages after Writes) unites and extends recent advances in binary code analysis and transformation to solve a longstanding compatibility problem for binary code security hardening algorithms—support for arbitrary dynamically self-modifying code. Self-modification is now a mainstay of many consumer software products, including Just-In-Time (JIT) compiled languages, on-demand component loading, self-extracting installers, and self-hooking APIs; but it poses significant challenges for code hardening algorithms that rely on computationally heavy static analyses, source code information, or compiler-specific code generation patterns. As a result, many of the strongest protection mechanisms for code hardening have remained incompatible or significantly weakened for the large class of software that incorporates self-modification (either directly or within its underlying runtime systems).

TrustScope is a new, a practical approach to identifying vulnerabilities in printer firmware without actually touching the firmware. By exploiting the trust between the firmware and the device drivers, TrustScope analyzes driver software to identify the driver endpoints that output the page description language (PDL) code to be sent to the printer, extracts key constraints for this output, generates new inputs violating these constraints, and fuzzes the printer firmware with malicious PDL code composed with these inputs yet conforming to the grammar of the PDL accepted by the printer. To accommodate the black-box nature of printers, printer behavior is observed strictly externally, allowing TrustScope to detect more vulnerabilities than only those that produce crashes. A variety of key optimizations, such as fuzzing without consuming paper and ink, and offline test case generation, make printer vulnerability detection feasible and practical. An implementation of TrustScope tested with 8 different printers reveals at least one test case causing anomalous behavior in every printer tested. For most printers it finds multiple vulnerabilities, 6 of which have been assigned CVE numbers, including buffer overflow and information disclosure.

Recent advances in trusted execution environments, specifically with Intel's introduction of SGX on consumer processors, have provided unprecedented opportunities to create secure applications with a small TCB. While a large number of SGX solutions have been proposed, nearly all of them focus on protecting native code applications, leaving scripting languages unprotected. To fill this gap, this paper presents SCRIPTSHIELD, a framework capable of running legacy script code while simultaneously providing confidentiality and integrity for scripting code and data. In contrast to the existing schemes that either require tedious and time-consuming re-development or result in a large TCB by importing an entire library OS or container, SCRIPTSHIELD keeps the TCB small and provides backwards compatibility (i.e., no changes needed to the scripting code itself). The core idea is to customize the script interpreter to run inside an SGX enclave and pass scripts to it. We have implemented SCRIPTSHIELD and tested with three popular scripting languages: Lua, JavaScript, and Squirrel. Our experimental results show that SCRIPTSHIELD does not cause noticeable overhead. The source code of SCRIPTSHIELD has been made publicly available as an open source project.

Intel SGX provides a secure enclave in which code and data are hidden from the outside world, including privileged code such as the OS or hypervisor. However, by default, enclave code prior to initialization can be disassembled and therefore no secrets can be embedded in the binary. This is a problem for developers wishing to protect code secrets. This paper introduces SGXElide, a nearly-transparent framework that enables enclave code confidentiality. The key idea is to treat program code as data and dynamically restore secrets after an enclave is initialized. SGXElide can be integrated into any enclave, providing a mechanism to securely decrypt or deliver the secret code with the assistance of a developer-controlled trusted remote party. We have implemented SGXElide atop a recently released version of the Linux SGX SDK, and our evaluation with a number of programs shows that SGXElide can be used to protect the code secrecy of practical applications with no overhead after enclave initialization.

System logs are the greatest forensics assets that capture how an operating system or a program behaves. System logs are often the next immediate attack target once a system is compromised, and it is thus paramount to protect them. This paper introduces SGX-Log, a new logging system that ensures the integrity and confidentiality of log data. The key idea is to redesign a logging system by leveraging a recent hardware extension, called Intel SGX, which provides a secure enclave with sealing and unsealing primitives to protect program code and data in both memory and disk from being modified in an unauthorized manner even from high privilege code. We have implemented SGX-Log atop the recent Ubuntu 14.04 for secure logging using real SGX hardware. Our evaluation shows that SGX-Log introduces no observable performance overhead to the programs that generate the log requests, and it also imposes very small overhead to the log daemons.