bug#45413: Password exposure on SSH login

bug#45413: Password exposure on SSH login

[Pedro J. V. Mendes via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Within <M-x shell>, on SSH login (e.g.) to sigma.ist.utl.pt, the 
password was
visible during typing and recorded to history (accessible through M-p).


In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, 
cairo version 1.16.0)
  of 2020-11-30 built on lcy01-amd64-021
Repository revision: b65eeac9613c62aaa0e4408dba8d795c07ea1f11
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12008000
System Description: Ubuntu 20.04.1 LTS

Recent messages:
C-x *  (Type ? for a list of Calc options)
Welcome to the GNU Emacs Calculator!  Press ‘?’ or ‘h’ for help, ‘q’ to quit
C-c M-p is undefined
ESC M-p is undefined
History item: 8
History item: 17 [3 times]
History item: 23
History item: 105
Mark saved where search started
~/Programs.dev
Quit
Configured using:
  'configure --prefix=/snap/emacs/current/usr --with-x-toolkit=gtk3
  --without-xaw3d --with-modules --with-cairo
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bug#45413: Password exposure on SSH login

[Unknown]

"Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
knife of text editors" <bug-gnu-emacs@gnu.org> writes:

> Within <M-x shell>, on SSH login (e.g.) to sigma.ist.utl.pt, the
> password was
> visible during typing and recorded to history (accessible through
> M-p).

Could you paste how the OpenSSH password prompt looks like in that
system?  Perhaps we need to update comint-password-prompt-regexp to
match it appropriately.

bug#45413: Password exposure on SSH login

[Unknown]

"Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
knife of text editors" <bug-gnu-emacs@gnu.org> writes:

> Within <M-x shell>, on SSH login (e.g.) to sigma.ist.utl.pt, the
> password was
> visible during typing and recorded to history (accessible through
> M-p).

Could you paste how the OpenSSH password prompt looks like in that
system?  Perhaps we need to update comint-password-prompt-regexp to
match it appropriately.

bug#45413: Password exposure on SSH login

[Unknown]

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"Pedro J. V. Mendes" <pedro.mendes@ist.utl.pt> writes:

[Don't forget to CC the bug tracker address so that the entire
conversation gets tracked. Thanks.]

> Hello, and happy Xmas!
>
> I give you snapshot of a minimal session exposing the problem.
>
> When I was typing the password, the characters were showing in
> normal-face, and after pressing Enter they turned to bold-face, like
> the previous "ssh" command.

Do you see at the bottom of the screen a minibuffer prompt that asks for
the password?  If you enter the password in that minibuffer prompt (not
in the shell buffer), it should replace characters with asterisks.  Make
sure you didn't accidentally switch from the minibuffer to the shell
buffer.

[Screenshot showing the problem, from the OP]


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Hm, it looks like a regular "Password:" OpenSSH prompt that should
already be handled correctly, unless I'm missing something.  Does this
happen when you start Emacs as "emacs -Q" too?

>
> After that both the "ssh" command and the password were recorded into
> the history.
>
> I hope this helps.
>

bug#45413: Password exposure on SSH login

[Pedro J. V. Mendes via Bug reports for GNU Emacs, the Swiss army knife of text editors]

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OK, (only) after starting with emacs -Q does the password prompt (and 
the focus) appear at the mini-buffer.

On 25/12/20 11:48, Daniel Martín wrote:
> "Pedro J. V. Mendes" <pedro.mendes@ist.utl.pt> writes:
>
> [Don't forget to CC the bug tracker address so that the entire
> conversation gets tracked. Thanks.]
>
>> Hello, and happy Xmas!
>>
>> I give you snapshot of a minimal session exposing the problem.
>>
>> When I was typing the password, the characters were showing in
>> normal-face, and after pressing Enter they turned to bold-face, like
>> the previous "ssh" command.
> Do you see at the bottom of the screen a minibuffer prompt that asks for
> the password?  If you enter the password in that minibuffer prompt (not
> in the shell buffer), it should replace characters with asterisks.  Make
> sure you didn't accidentally switch from the minibuffer to the shell
> buffer.
>
> [Screenshot showing the problem, from the OP]
>
>
> Hm, it looks like a regular "Password:" OpenSSH prompt that should
> already be handled correctly, unless I'm missing something.  Does this
> happen when you start Emacs as "emacs -Q" too?
>
>> After that both the "ssh" command and the password were recorded into
>> the history.
>>
>> I hope this helps.
>>

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bug#45413: Password exposure on SSH login

[Unknown]

"Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
knife of text editors" <bug-gnu-emacs@gnu.org> writes:

> OK, (only) after starting with emacs -Q does the password prompt (and
> the focus) appear at the mini-buffer.
>

Yes, that is expected.  The minibuffer prompt should hide your password
with asterisks as you type it.

I think this may not be a bug in Emacs, but a problem somewhere in your
Emacs configuration.  Comment out parts of your .emacs until you find
the culprit.

bug#45413: Password exposure on SSH login

[Unknown]

"Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
knife of text editors" <bug-gnu-emacs@gnu.org> writes:

> OK, (only) after starting with emacs -Q does the password prompt (and
> the focus) appear at the mini-buffer.
>

Yes, that is expected.  The minibuffer prompt should hide your password
with asterisks as you type it.

I think this may not be a bug in Emacs, but a problem somewhere in your
Emacs configuration.  Comment out parts of your .emacs until you find
the culprit.

bug#45413: Password exposure on SSH login

[João Távora]

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When I studied at that university, shared machines were a thing. I didn't
know if they are still, but I'd also try with:

emacs -q # that's lowercase q

If the problem still happens, it's likely in the site-start.el , and not in
.emacs

https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html#Init-File

João

On Fri, Dec 25, 2020, 20:46 Daniel Martín via Bug reports for GNU Emacs,
the Swiss army knife of text editors <bug-gnu-emacs@gnu.org> wrote:

> "Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
> knife of text editors" <bug-gnu-emacs@gnu.org> writes:
>
> > OK, (only) after starting with emacs -Q does the password prompt (and
> > the focus) appear at the mini-buffer.
> >
>
> Yes, that is expected.  The minibuffer prompt should hide your password
> with asterisks as you type it.
>
> I think this may not be a bug in Emacs, but a problem somewhere in your
> Emacs configuration.  Comment out parts of your .emacs until you find
> the culprit.
>
>
>
>

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bug#45413: Password exposure on SSH login

[Pedro J. V. Mendes via Bug reports for GNU Emacs, the Swiss army knife of text editors]

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In my system, only with―from man emacs―“
             -Q, --quick
                       Similar  to  "-q --no-site-file --no-splash".  
Also, avoid processing X re‐
                       sources.
” is the prompt transferred to the minibuffer.

I'll check and tweak the startup configuration.

Thanks!

On 25/12/20 21:29, João Távora wrote:
> When I studied at that university, shared machines were a thing. I 
> didn't know if they are still, but I'd also try with:
>
> emacs -q # that's lowercase q
>
> If the problem still happens, it's likely in the site-start.el , and 
> not in .emacs
>
> https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html#Init-File
>
> João
>
> On Fri, Dec 25, 2020, 20:46 Daniel Martín via Bug reports for GNU 
> Emacs, the Swiss army knife of text editors <bug-gnu-emacs@gnu.org 
> <mailto:bug-gnu-emacs@gnu.org>> wrote:
>
>     "Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
>     knife of text editors" <bug-gnu-emacs@gnu.org
>     <mailto:bug-gnu-emacs@gnu.org>> writes:
>
>     > OK, (only) after starting with emacs -Q does the password prompt
>     (and
>     > the focus) appear at the mini-buffer.
>     >
>
>     Yes, that is expected.  The minibuffer prompt should hide your
>     password
>     with asterisks as you type it.
>
>     I think this may not be a bug in Emacs, but a problem somewhere in
>     your
>     Emacs configuration.  Comment out parts of your .emacs until you find
>     the culprit.
>
>
>

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bug#45413: Password exposure on SSH login

[João Távora]

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I'm not 100% sure I follow, but just to underline what I said before: if
the system behaves as expected with -Q but not with
lowercase -q then that clearly points to the system-wide shared
site-start.el file, not the user's init file.

That's because '-q' inhibits the latter, but not the former.

João

On Fri, Dec 25, 2020, 21:46 Pedro J. V. Mendes <pedro.mendes@ist.utl.pt>
wrote:

> In my system, only with―from man emacs―“
>              -Q, --quick
>                       Similar  to  "-q --no-site-file --no-splash".  Also,
> avoid processing X re‐
>                       sources.
> ” is the prompt transferred to the minibuffer.
>
> I'll check and tweak the startup configuration.
>
> Thanks!
> On 25/12/20 21:29, João Távora wrote:
>
> When I studied at that university, shared machines were a thing. I didn't
> know if they are still, but I'd also try with:
>
> emacs -q # that's lowercase q
>
> If the problem still happens, it's likely in the site-start.el , and not
> in .emacs
>
>
> https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html#Init-File
>
> João
>
> On Fri, Dec 25, 2020, 20:46 Daniel Martín via Bug reports for GNU Emacs,
> the Swiss army knife of text editors <bug-gnu-emacs@gnu.org> wrote:
>
>> "Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
>> knife of text editors" <bug-gnu-emacs@gnu.org> writes:
>>
>> > OK, (only) after starting with emacs -Q does the password prompt (and
>> > the focus) appear at the mini-buffer.
>> >
>>
>> Yes, that is expected.  The minibuffer prompt should hide your password
>> with asterisks as you type it.
>>
>> I think this may not be a bug in Emacs, but a problem somewhere in your
>> Emacs configuration.  Comment out parts of your .emacs until you find
>> the culprit.
>>
>>
>>
>>

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bug#45413: Password exposure on SSH login

[Pedro J. V. Mendes via Bug reports for GNU Emacs, the Swiss army knife of text editors]

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Thanks for the distinction and clarification. By thw way, I've just find 
that such issue occurs only with GUI Emacs! With Emacs running within a 
terminal (Konsole) everything works as expected, i.e. without any 
command-line arguments (oher than -nw) the prompt is transferred to the 
minibuffer.

On 25/12/20 21:59, João Távora wrote:
> I'm not 100% sure I follow, but just to underline what I said before: 
> if the system behaves as expected with -Q but not with
> lowercase -q then that clearly points to the system-wide shared 
> site-start.el file, not the user's init file.
>
> That's because '-q' inhibits the latter, but not the former.
>
> João
>
> On Fri, Dec 25, 2020, 21:46 Pedro J. V. Mendes 
> <pedro.mendes@ist.utl.pt <mailto:pedro.mendes@ist.utl.pt>> wrote:
>
>     In my system, only with―from man emacs―“
>                 -Q, --quick
>                           Similar  to  "-q --no-site-file
>     --no-splash".  Also, avoid processing X re‐
>                           sources.
>     ” is the prompt transferred to the minibuffer.
>
>     I'll check and tweak the startup configuration.
>
>     Thanks!
>
>     On 25/12/20 21:29, João Távora wrote:
>>     When I studied at that university, shared machines were a thing.
>>     I didn't know if they are still, but I'd also try with:
>>
>>     emacs -q # that's lowercase q
>>
>>     If the problem still happens, it's likely in the site-start.el ,
>>     and not in .emacs
>>
>>     https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html#Init-File
>>
>>     João
>>
>>     On Fri, Dec 25, 2020, 20:46 Daniel Martín via Bug reports for GNU
>>     Emacs, the Swiss army knife of text editors
>>     <bug-gnu-emacs@gnu.org <mailto:bug-gnu-emacs@gnu.org>> wrote:
>>
>>         "Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the
>>         Swiss army
>>         knife of text editors" <bug-gnu-emacs@gnu.org
>>         <mailto:bug-gnu-emacs@gnu.org>> writes:
>>
>>         > OK, (only) after starting with emacs -Q does the password
>>         prompt (and
>>         > the focus) appear at the mini-buffer.
>>         >
>>
>>         Yes, that is expected.  The minibuffer prompt should hide
>>         your password
>>         with asterisks as you type it.
>>
>>         I think this may not be a bug in Emacs, but a problem
>>         somewhere in your
>>         Emacs configuration.  Comment out parts of your .emacs until
>>         you find
>>         the culprit.
>>
>>
>>

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bug#45413: Password exposure on SSH login

[Stefan Kangas]

tags 45413 + moreinfo
thanks

"Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
knife of text editors" <bug-gnu-emacs@gnu.org> writes:

> OK, (only) after starting with emacs -Q does the password prompt (and
> the focus) appear at the mini-buffer.

So it looks like we need more information here to reproduce this bug.

Could you please report back when you find out what part of the site
configuration leads to this bug?  Thanks in advance.

bug#45413: Password exposure on SSH login

[Pedro J. V. Mendes via Bug reports for GNU Emacs, the Swiss army knife of text editors]

OK, I'll try to figure it out.

On 28/12/20 07:21, Stefan Kangas wrote:
> tags 45413 + moreinfo
> thanks
>
> "Pedro J. V. Mendes" via "Bug reports for GNU Emacs, the Swiss army
> knife of text editors" <bug-gnu-emacs@gnu.org> writes:
>
>> OK, (only) after starting with emacs -Q does the password prompt (and
>> the focus) appear at the mini-buffer.
> So it looks like we need more information here to reproduce this bug.
>
> Could you please report back when you find out what part of the site
> configuration leads to this bug?  Thanks in advance.

bug#45413: Password exposure on SSH login

[Lars Ingebrigtsen]

"Pedro J. V. Mendes" <pedro.mendes@ist.utl.pt> writes:

> OK, I'll try to figure it out.

[...]

>> Could you please report back when you find out what part of the site
>> configuration leads to this bug?  Thanks in advance.

More information was requested, but no response was given within a
month, so I'm closing this bug report.  If the problem still exists,
please respond to this email and we'll reopen the bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no