$ ctf42

Vectorial_RSA

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In the final days of the Roman civil war, two rival generals, Alicius and Bobius, sought to end the bloodshed. Each commanded legions, loyal to none but themselves, yet both knew that if they continued to fight, Rome itself would fall.

One evening, under the dim glow of torches in a secret chamber beneath the Senate, they made a pact.

"We shall forge an agreement so intricate," Alicius declared, "that neither of us can betray the other without dooming ourselves!"

Bobius nodded. "A contract not written in ink, but in mathematics. A key split between us, each holding only half, bound by powers so great no single man could claim the full prize."

The plan was set.

Each general secretly constructed their own half of the key, twisting numbers with their private parameters, raising their secrets to powers unfathomable, and encrypting their half with the other's public strength. Neither would possess the full key until the pact was honored.

The final message was sealed. A shared key was formed. A cipher was drawn over the most precious secret of Rome.

"With this," Alicius whispered, "we ensure balance. No betrayal, no treachery. Only unity."

But as the torches flickered, unseen figures moved in the shadows. The Numerii watched. The pact was clever, but cleverness alone would not save it. The scheme had flaws—subtle, imperceptible, yet fatal.

And when the time came, the twin generals would learn:

A pact sealed in numbers can be undone in numbers.

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