Re: Request to Update OpenSSH Version in Git due to Security Vulnerabilities (CVE-2006-5051, CVE-2024-6387

[Dragan Simic <dsimic@manjaro.org>]

Hello Johannes,

On 2024-07-22 11:38, Johannes Schindelin wrote:
> On Wed, 10 Jul 2024, 'Dragan Simic' via Git Security wrote:
> 
>> On 2024-07-10 19:10, Junio C Hamano wrote:
>> > Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>> >
>> > > The crucial part is the `sshd` part. Git for Windows does distribute the
>> > > `sshd.exe` binary, but it is in no way used by default, nor is there
>> > > support how to set it up to run an SSH server.
>> > >
>> > > Git for Windows is therefore not affected by this vulnerability, and
>> > > therefore it is not crucial to get a new version out as quickly as
>> > > possible. See also my assessment at
>> > > https://github.com/git-for-windows/git/issues/5031#issuecomment-2199722969
>> >
>> > I think I've seen in the past another inquiry about vulnerability
>> > in OpenSSH, which turned out to be irrelevant in the context of Git
>> > for Windows for this exact reason (i.e. "sshd" is problematic but
>> > "ssh" is OK).
>> >
>> > Would it make future confusion like this less likely if you stopped
>> > shipping the sshd and ship only the ssh client?
>> 
>> Not shipping sshd.exe would make sense regardless of the associated 
>> security
>> issues, because it would prevent accidental enabling of SSH access.
> 
> There is little accidental about starting `sshd` after generating a 
> valid
> host key.

Well, I don't know what and how Git for Windows does regarding the host
key generation, so the possibility of accidental starting the shipped
sshd.exe may actually be quite low.

> Having said that, `sshd` is not required to run Git, therefore it 
> should
> not be distributed with Git for Windows. This PR addresses that:
> https://github.com/git-for-windows/build-extra/pull/571

Interestingly, that pull request shows that some people actually use(d)
the shipped sshd.exe, which just shows that nearly every change will
inevitably break somebody's workflow.