Limits RegistryPUBLIC RECORD
Limits RegistryIn February 2017, Google and the CWI Amsterdam research institute jointly announced 'SHAttered,' the first publicly demonstrated practical collision in the SHA-1 cryptographic hash function — two distinct PDF files that hash to the same SHA-1 digest. The attack required an estimated 9,223,372,036,854,775,808 SHA-1 computations, equivalent to roughly 6,500 CPU-years and 100 GPU-years of computation, and accelerated the industry-wide migration away from SHA-1 that standards bodies had already been recommending since the mid-2000s.
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In February 2017, Google and the CWI Amsterdam research institute jointly announced 'SHAttered,' the first publicly demonstrated practical collision in the SHA-1 cryptographic hash function — two distinct PDF files that hash to the same SHA-1 digest. The attack required an estimated 9,223,372,036,854,775,808 SHA-1 computations, equivalent to roughly 6,500 CPU-years and 100 GPU-years of computation, and accelerated the industry-wide migration away from SHA-1 that standards bodies had already been recommending since the mid-2000s.
The first publicly demonstrated pair of distinct inputs producing an identical SHA-1 hash digest, breaking SHA-1's collision resistance in practice rather than merely in theory.
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The frontier as it changed over time.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-SHA1-SHATTERED-COLLISION
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Limits Registry. LR-SHA1-SHATTERED-COLLISION. First publicly demonstrated practical collision in the SHA-1 hash function. 2026.