From: Vincent Bernat <bernat@luffy.cx>
To: dana <dana@dana.is>
Cc: zsh-users@zsh.org
Subject: Re: CVE-2021-45444 really fixed in 5.8.1?
Date: Sat, 12 Mar 2022 23:58:57 +0100 [thread overview]
Message-ID: <m3pmmqok0e.fsf@luffy.cx> (raw)
In-Reply-To: <8e5ef93a-85b0-4a04-9b3a-01452f29e68f@www.fastmail.com> (dana@dana.is's message of "Sat, 12 Mar 2022 16:45:11 -0600")
❦ 12 March 2022 16:45 -06, dana:
>> Is CVE-2021-45444 really fixed in 5.8.1?
>>
>> ...
>>
>> %1 was interpreted while it shouldn't have been?
>>
>> The provided workaround for older versions work fine.
>
> The issue that was fixed in 5.8.1 is that PROMPT_SUBST evaluation was being
> performed in the arguments to e.g. %F. This is not specifically related to
> VCS_Info, but it was the most likely place it could cause trouble. e.g.
> checking out a git branch name containing %F{...} could have resulted in
> arbitrary code execution given a typical VCS_Info configuration. It was
> fixed by simply not performing PROMPT_SUBST evaluation in that context any
> more.
You mean, it was possible to do "%F{$(echo hello)}"?
Thanks for the remaining explanation!
--
All generalizations are false, including this one.
-- Mark Twain
next prev parent reply other threads:[~2022-03-12 22:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-12 14:39 Vincent Bernat
2022-03-12 22:45 ` dana
2022-03-12 22:58 ` Vincent Bernat [this message]
2022-03-13 0:01 ` dana
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=m3pmmqok0e.fsf@luffy.cx \
--to=bernat@luffy.cx \
--cc=dana@dana.is \
--cc=zsh-users@zsh.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/zsh/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).