Source: Mitre, NVD – Published: 2026-09-12
Preface: Automotive & Safety-Critical SystemsIn industries where software must comply with rigid safety certifications (such as ISO 26262 for automotive or DO-178C for aerospace), executing arbitrary code at runtime using a Just-In-Time (JIT) compiler is completely forbidden.
The wasm2c Advantage: Since wasm2c acts entirely as an Ahead-Of-Time (AOT) translator converting bytecode into standard source code, the output can be completely audited by static analysis tools, checked for safety flaws, and bundled cleanly into a deterministic, monolithic native binary before deployment.
Background: The technical synergy between ISO 26262 requirements and a tool like wasm2c from the WebAssembly Binary Toolkit (WABT) is highly relevant in modern automotive engineering.
Does Tesla use WebAssembly?Yes. Tesla engineers have publicly spoken about using WebAssembly. For example, Tesla uses Wasm to move processing workloads flexibly between the Tesla Cloud and the Vehicle Edge. When deploying these components into microcontrollers or vehicle telematics, converting bytecode into native static C code (via wasm2c or similar AOT compilers like Lucet or WAMR) is exactly how they maintain the performance of bare-metal C while keeping the safety boundaries of WebAssembly.
Ref: By using wasm2c, an automotive engineer can bypass the JIT problem completely:
wasm2c restricts the WebAssembly code to a strictly bounded linear memory array. It translates Wasm memory bounds-checks into standard static C checks, drastically reducing the risk of buffer overflows—a core requirement of ISO 26262 Part 6 (Software Product Development).
Vulnerability details: CVE-2026-90648 details a critical sandbox escape vulnerability within the WebAssembly Binary Toolkit (WABT) compiler framework (wasm2c) version 1.0.41 and earlier [CVE-2026-90648]. In modern automotive Over-the-Air (OTA) deployment models, wasm2c is heavily relied upon to translate platform-independent WebAssembly binaries into static, deterministic C shared libraries (.so), which are then dynamically loaded into running vehicles via standard OS utilities (dlopen) to bypass strict Just-In-Time (JIT) runtime compiler bans. However, a major validation oversight within the toolkit’s native runtime implementation causes the core function pointer (funcref) table allocation routine to entirely ignore memory allocation allocation failures (such as a NULL return from calloc). Because the engine fails to detect this error, it registers the module’s boundary limits as valid while leaving the base memory destination pointing directly to NULL (0x0). Consequently, subsequent indirect call checks fail to trigger, allowing an attacker or a faulty isolated script to execute absolute address memory read/writes at 0x0 + index, resulting in complete host sandbox escape and the potential hijacking of vehicle telemetry or system control pipelines.
Official announcement: Please refer to the link for details – https://www.tenable.com/cve/CVE-2026-90648