Ken Thompson’s 1980 Unix password got cracked only a while ago: he used much entropy in his password
Posted by jpluimers on 2021/07/22
A few years back, Ken Thompson’s 1980 Unix password got cracked.
It took that long because his password p/q2-q4!
had enough entropy by using uncommon characters so the crypt(3) based hash ZghOT0eRm4U9s
was hard to crack.
The password was an opening chess move noted in the variety of the descriptive notation. A shorter notation would have been P-Q4, which would require months to crack in that era.
In modern chess notation, it would be 1. d4
, moving the Queen’s Pawn from d2 to d4.
References (many interesting messages in the TUHS thread below):
- [WayBack] unix-history-repo/passwd at BSD-3-Snapshot-Development · dspinellis/unix-history-repo · GitHub
- [WayBack] leah blogs: Ken Thompson’s Unix password
- [WayBack] Ken Thompson’s Unix password #VintageComputing #History #Unix « Adafruit Industries – Makers, hackers, artists, designers and engineers!
- [WayBack] Ken Thompson – Chessprogramming wiki
- [WayBack] Fefes Blog: Wed Oct 9 2019
- [WayBack] Descriptive notation – Wikipedia
- [WayBack] Chess Opening Theory/1. d4 – Wikibooks, open books for an open world
- [WayBack] The Unix Heritage Society
- [WayBack] The Unix Heritage Society mailing list
- [WayBack] [TUHS] Recovered /etc/passwd files
From: Finn O'Leary @ 2019-10-03 18:51 UTC (permalink / raw) To: The Eunuchs Hysterical Society Hi, I remember that someone had recovered some ancient /etc/passwd files and had decrypted(?) them, and I remember reading that either ken or dmr's password was something interesting like './,..,/' (it was entirely punctuation characters, was around three different characters in total, and was pretty damn short). I've tried to find this since, as a friend was interested in it, and I cannot for the life of me find it! Do any of you remember or have a link? :) Thanks! -- "Too enough is always not much!"
- [WayBack] Re: [TUHS] Recovered /etc/passwd files – Nigel Williams
From: Nigel Williams <nw@retrocomputingtasmania.com> Cc: TUHS main list <tuhs@minnie.tuhs.org> Subject: Re: [TUHS] Recovered /etc/passwd files Date: Wed, 9 Oct 2019 16:49:48 +1100 Message-ID: <CACCFpdx_6oeyNkgH_5jgfxbxWbZ6VtOXQNKOsonHPF2=747ZOw@mail.gmail.com> (raw) In-Reply-To: <8088e5bd-3530-d3e1-8066-db6ea9389dea@kilonet.net> ken is done: ZghOT0eRm4U9s:p/q2-q4! took 4+ days on an AMD Radeon Vega64 running hashcat at about 930MH/s during that time (those familiar know the hash-rate fluctuates and slows down towards the end).
- [WayBack] Re: [TUHS] Recovered /etc/passwd files – Andy Kosela
From: Andy Kosela <akosela@andykosela.com> To: Warner Losh <imp@bsdimp.com> Cc: TUHS main list <tuhs@minnie.tuhs.org> Subject: Re: [TUHS] Recovered /etc/passwd files Date: Wed, 9 Oct 2019 10:16:02 +0200 Message-ID: <CALMnNGgVFHiBz5n0YZq8FiMt=iVN0t4dKKzCrKHk25fdq+0w7A@mail.gmail.com> (raw) In-Reply-To: <CANCZdfoaUm-FTDhBk05zQ_CTdEQ2y1uw9irQpxqzSVgOCUMjbQ@mail.gmail.com> On 10/9/19, Warner Losh <imp@bsdimp.com> wrote: > On Tue, Oct 8, 2019, 11:52 PM Nigel Williams > <nw@retrocomputingtasmania.com> > wrote: > >> On Wed, Oct 9, 2019 at 4:49 PM Nigel Williams >> <nw@retrocomputingtasmania.com> wrote: >> > ZghOT0eRm4U9s:p/q2-q4! >> >> BTW, is that a chess move? >> > > Most common opening. > Descriptive chess notation is not as popular today as it was back in the 70s, but it actually makes perfect sense as Ken is a long time chess enthusiast. --Andy
Via:
- [WayBack] Leah die Schreckliche 👻 di Twitter: “Enjoy: Ken Thompson’s Unix password”
-
[WayBack] adafruit industries on Twitter: “Ken Thompson’s Unix password #VintageComputing #History #Unix”
–jeroen
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