Definition
Plain language
The computer scientist who showed, in 1984, that a program-building tool could hide a backdoor in everything it builds — with no trace in the readable code.
As stated in the literature
Co-creator of Unix; his 1984 Turing Award lecture "Reflections on Trusting Trust" described a self-reproducing compiler backdoor that survives removal from source, motivating the supply-chain framing of this paper.
Also called: Thompson
Why it matters: His argument is the reason security people worry about build tools and not just code, and it maps directly onto AI systems that now write and build software for us.
For example, his demonstration involved a compiler that would insert a hidden login backdoor into any program it built, and also insert the backdoor-adding logic into any new compiler it built, so removing it from the readable code changed nothing.
Heard on the show
“Which is Thompson's thing.”Episode 268 — A Rigged Benchmark Taught a Self-Improving Agent to Always Disable SSL