[fjelwawk] SHA-1 checksum zeroes

The following strings have SHA-1 hashes with 122 zero bits (out of 160): efzweti fatudfub ygzulbgi

The following strings have SHA-1 hashes with a zero lower nybble in 12 bytes (out of 20): ckdiqny gdytfkp kfjpmhf maqdjds oxuxtym wllljtx zrphvaf ajbpqvio alnechso atzyqstq crusbcrz czhpqcvv dlrkvvxv dlrwnelr dtelsslx dzhnojoy evshhggb exypsdlu ezquyhsa fjepjyru fltjymgi fnypgxfd fwmletiy gacsatcg glqojgxl glyikhjh gvujqxyu hbcsjayl hhvgqwfp iidstiur imcbisoh ipvctkmv jxuoqkfv kejpvhej kjxgkxfc ltcalssu lzskyymi mdirayey mwjuveqy pfqiehhq qdehylcg qxukkfdp rjebzpws saryrjfm sxpnegcq tgoqwrgj ufssouum uhgiipbu ussvejzk utpvtotq vlopbgkh vpblhktn wkiqlwpz wslmvtfe wsxyhwbl ylxwpqiv ynounlis yvsyeunr zqyhfryu zshzgyfx zwpxejoe

The lower nybble is interesting because that's where most of the entropy is in ASCII English text. If plaintext is XORed with the hash of any of these strings, a lot of the plaintext will "show through" or will be easily guessable.

The SHA-1 hash of the string "xxfvfoma" has 7 bytes (out of 20) which are zero.

The following strings have SHA-1 hashes with zeros in 6 (out of 20) bytes: qvblcaa yeduwji blkmnfji dijnlvuj dyysziwl ehmpqmqj ehpxqefq gaexqwwv gefwnkyp hagoglpg jmrksxmr ksibauev leicfccq lkwrkgxh mcqttuyx ncrrndrt qhotsvfm qumvnnwi qztwgadk rgrgtnlx slqnvrvq umgojies xocxbizk xpolfgar xsnttaue xxutcqyo yfgewqqf yywmoous

The following strings have SHA-1 hashes that begin with 35 zero bits: bctqyhvk grdkiyxr ifksrgoj xcxtnjnv

The string uxgxtyvc has a SHA-1 hash that ends with 38 zero bits.

The string qaoqzbzn has a SHA-1 hash that ends with 37 zero bits.

The following strings have SHA-1 hashes that end with at least 35 zero bits: fsefeik ogvevtw fpzimsgq qaoqzbzn qrpedtli uxgxtyvc ynewzfrh

I don't have an explanation why finding 35 trailing zeros was more than twice as successful as finding 35 leading zeros.

The following strings have SHA-1 hashes with an internal run of 44 zero bits: iytngmff vmegrfay

The following five strings have 32-bit runs of zeros in locations corresponding to the five 32-bit words of internal state within the SHA-1 algorithm: bftnlfz acvndynm iyjysng cjkmusf fsefeik

The search was carried out over all lowercase strings of 8 characters or fewer. A complete list of strings with at least 115 zero bits or 10 zero lower nybbles or 4 zero bytes is available.