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RSA·easy·15 pts

The Fastest Cipher

An engineer wanted RSA encryption without the performance cost. They found a way.

"RSA is too slow for our use case," the commit message says, "so I set e = 1 — same security, way faster." The pull request was approved.

Here's the "ciphertext" they're using in production.

Ciphertext (decimal integer)

54346890045854400693635193847915839177343981221943352407185784970053957584700833987772292323202591869

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Background on this technique

Up next

Too Close for Comfort →

A flawed key generator picked two primes that are suspiciously close together. This is scriptable in a few lines.