Thanks Ben, 

I’ve only had half a cup of coffee this am, so it’s possible I’m not yet awake 
:)

I have a question about reasons 2 and 3 as they’re closely related to the 
attack vector.

According to Google, spear phishing attacks have a shelf life of 7 minutes 
while bulk campaigns have a shelf life of 13 hours. Even if we disbelieve this 
data and multiple the numbers by 10, we end up with the majority of the harm 
being done within a week. 

Also, if bad actors can automatically acquire a DV cert for any available 
domain they please, is there actual risk of bad actors waiting for a domain to 
expire so they can have a valid cert? And they can easily execute a 
man-in-the-middle attack using a new cert that has a shelf life of 3 months.

All I’ve been working on for years is anti-phishing techniques, so I’m not 
seeing all of the benefits as some others see them, but perhaps I’m missing 
something.

I’m talking about the human element of bad actors here, because at the end of 
the day, it’s all about them and what they will do with expired certs. 

If we were talking about EV I’d see every single benefit as described, but not 
for DV. When I look at our phishing data, the reasons provided for reducing the 
shelf life of DV outweighs the cost. 

There is a cost to website owners. I’d argue it’s an expensive exercise. CAs 
stand to generate more revenue by shortening the life of a cert, so I don’t 
know what their motivates could be to fight against this change - aside from 
wanting to support their customers (website owners). There was no consensus in 
the CA/Browser Forum - CAs voted against this change.

For those who think I love CAs, my company displaces the need for EV, so I’m 
certainly not fighting on their behalf. I just don’t see the benefits as 
browser vendors see them, and there is still no data that I can find, to help 
me better understand the fine details of points 2 and 3.

I believe browser vendors have the right to enforce what they deem appropriate. 
I’m simply asking for more details given that you’re engaging with the 
community.

Thanks,
Paul




> On Jul 9, 2020, at 8:46 AM, Ben Wilson via dev-security-policy 
> <dev-security-policy@lists.mozilla.org> wrote:
> 
> All,
> This is just to let everyone know that I posted a new Mozilla Security blog
> post this morning. Here is the link>
> https://blog.mozilla.org/security/2020/07/09/reducing-tls-certificate-lifespans-to-398-days/
> As I note at the end of the blog post, we continue to seek safeguarding
> secure browsing by working with CAs as partners, to foster open and frank
> communication, and to be diligent in looking for ways to keep our users
> safe.
> Thanks,
> Ben
> _______________________________________________
> dev-security-policy mailing list
> dev-security-policy@lists.mozilla.org
> https://lists.mozilla.org/listinfo/dev-security-policy

_______________________________________________
dev-security-policy mailing list
dev-security-policy@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-security-policy

Reply via email to