arXiv subjects

Dominik Maier

Publications and source records attributed to Dominik Maier.

2 recordsLinked to original sources

arXiv2026

CodeMechanic: Bug-Property-Guided Program Mitigation

Automated testing discovers vulnerabilities faster than developers can investigate and repair them, leaving an interval in which known memory corruptions remain exploitable. End- to-end LLM repair agents can shorten this interval, but they synthesize open-ended code changes and commonly validate them only by replaying a proof of concept (PoC). This weak oracle accepts patches that silence the observed crash by changing unrelated behavior, making unintended deployment risky. We present CodeMechanic, a bug-property-guided system for generating constrained mit- igations for spatial memory corruption. Instead of asking an LLM to generate a permanent repair, CodeMechanic reconstructs the violated memory-safety property from the crash, validates the dereferenced pointer and its buffer range, and inserts a local fail-stop guard before the dangerous access. The guard terminates execution when the boundary check fails. The resulting mitigation deliberately trades availability for security: it can convert potential remote code execution into controlled termination while developers investigate the root cause and prepare a permanent repair. CodeMechanic combines a two-dimensional static and dynamic context extractor with in-prompt debugging knowledge and stepwise val- idation to limit the effect of LLM errors. On 101 real-world ARVO bugs, the first attempt of CodeMechanic produces 47.6% more plausible patches (i.e., patches that pass PoC- replay validation) than the best baseline while using 91% fewer tokens. Manual audit further shows that CodeMechanic produces 3.4x - 4.3x more patches semantically equivalent to developer-written repairs.

cs.SE↗

arXiv2020

BaseSAFE: Baseband SAnitized Fuzzing through Emulation

Rogue base stations are an effective attack vector. Cellular basebands represent a critical part of the smartphone's security: they parse large amounts of data even before authentication. They can, therefore, grant an attacker a very stealthy way to gather information about calls placed and even to escalate to the main operating system, over-the-air. In this paper, we discuss a novel cellular fuzzing framework that aims to help security researchers find critical bugs in cellular basebands and similar embedded systems. BaseSAFE allows partial rehosting of cellular basebands for fast instrumented fuzzing off-device, even for closed-source firmware blobs. BaseSAFE's sanitizing drop-in allocator, enables spotting heap-based buffer-overflows quickly. Using our proof-of-concept harness, we fuzzed various parsers of the Nucleus RTOS-based MediaTek cellular baseband that are accessible from rogue base stations. The emulator instrumentation is highly optimized, reaching hundreds of executions per second on each core for our complex test case, around 15k test-cases per second in total. Furthermore, we discuss attack vectors for baseband modems. To the best of our knowledge, this is the first use of emulation-based fuzzing for security testing of commercial cellular basebands. Most of the tooling and approaches of BaseSAFE are also applicable for other low-level kernels and firmware. Using BaseSAFE, we were able to find memory corruptions including heap out-of-bounds writes using our proof-of-concept fuzzing harness in the MediaTek cellular baseband. BaseSAFE, the harness, and a large collection of LTE signaling message test cases will be released open-source upon publication of this paper.

cs.CR↗