Subject: bug#36154: 26.2; read-passwd function creates a security issue

From: Ahmet BASTUG <[email-masked]>
Date: Sun, 9 Jun 2019 23:01:52 +0300

read-passwd function which is located in "subr.el" causes kind of a 
security issue. When function is used, user is prompted with a promt and 
everything user typed is displayed as '.' characters. If any kind of 
kill operation is performed on the prompt minibuffer, real value is 
saved into kill-ring. Then you can yank it anywhere you want. I'm not 
sure this is meant this way but I think not.

--text follows this line--

In GNU Emacs 26.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.8)
  of 2019-04-12 built on juergen
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description:    Manjaro Linux

Recent messages:
Type C-c C-c to finish, or C-c C-k to cancel
When done with a buffer, type C-c C-c
Saving file /home/kosantosbik/projects/bot/.git/COMMIT_EDITMSG...
Wrote /home/kosantosbik/projects/bot/.git/COMMIT_EDITMSG
Git finished
Running git push -v origin master:refs/heads/master
Git finished
C-x C-g is undefined
""
Mark set

Configured using:
  'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
--localstatedir=/var --with-x-toolkit=gtk3 --with-xft --with-modules
'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong
-fno-plt' CPPFLAGS=-D_FORTIFY_SOURCE=2
LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now'

Configured features:
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NOTIFY ACL GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 XDBE XIM MODULES THREADS LIBSYSTEMD LCMS2

Important settings:
   value of $LC_MONETARY: tr_TR.UTF-8
   value of $LC_NUMERIC: tr_TR.UTF-8
   value of $LC_TIME: tr_TR.UTF-8
   value of $LANG: en_US.UTF-8
   locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

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   prettify-symbols-mode: t
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   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t
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   column-number-mode: t
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   transient-mark-mode: t

Load-path shadows:
None found.

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