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   Terence Eden (edent@mastodon.social)'s status on Friday, 08-Mar-2024 19:29:44 JST Terence Eden

   On a related note, I'm *sure* I read a paper / post where someone proved that you could manipulate a file to produce a hash where the first and last few characters matched the hash of an unrelated file.

   Anyone know what I'm talking about?

   #Cryptography #Security

   • Embed this notice
     Ryan Castellucci :nonbinary_flag: (ryanc@infosec.exchange)'s status on Friday, 08-Mar-2024 19:29:43 JST Ryan Castellucci :nonbinary_flag:

     in reply to

     • David Buchanan

     @Edent Paging @retr0id

     This is trivial to do.

   • Embed this notice
     Terence Eden (edent@mastodon.social)'s status on Friday, 08-Mar-2024 19:34:27 JST Terence Eden

     in reply to

     • David Buchanan
     • Ryan Castellucci :nonbinary_flag:

     @ryanc @retr0id
     Oh, sure, the sha256 of "b" and "e" both start with "3".
     But I'm sure I read something about manipulating the first and last 5(?) characters.
     It is entirely possible I dreamt it though.

   • Embed this notice
     Ryan Castellucci :nonbinary_flag: (ryanc@infosec.exchange)'s status on Friday, 08-Mar-2024 19:34:27 JST Ryan Castellucci :nonbinary_flag:

     in reply to

     • David Buchanan

     @Edent @retr0id Controlling the first and last 5 characters is doable with brute force.

   • Embed this notice
     Jernej Simončič � (jernej__s@infosec.exchange)'s status on Friday, 08-Mar-2024 23:02:42 JST Jernej Simončič �

     in reply to

     • David Buchanan
     • Ryan Castellucci :nonbinary_flag:

     @ryanc @Edent @retr0id It's been demonstrated to be possible, mainly because when people compare hashes (visually), they usually only look at the first and last few characters.