mcpherrinm

14 ms·

91.
by mcpherrinm 1y ago
The downgrade attacks on TLS are only really present in the case of client behaviour where, on failing to achieve one version, they retry a new connection without it. This was necessary to bypass various broken server side implementations,
92.
by mcpherrinm 1y ago
Yes, ISPs absolutely do deep packet inspection. With cleartext DNS, your queries may never reach your chosen server. Plenty of ISPs are configured to just answer any DNS query, regardless of its destination. Using a nonstandard port might h
93.
by mcpherrinm 1y ago
The most important part of DoH, etc is that it allows you to make a choice. You can choose a vendor in your country. As a Canadian, I might want to use the service offered by my national TLD operator https://www.cira.ca/en&#
94.
by mcpherrinm 1y ago
Everything is an object, identified by a URL. You start from a single URL (the directory), and you can find all the rest of the resources from URLs provided from there. ACME models everything as JSON objects, each of which is identified by
95.
by mcpherrinm 1y ago
I'd take ASN.1/DER over JWS any day :) It's the weekend and I don't feel I have the energy to launch a full roast of JWS, but to give some flavour, I'll link https://auth0.com/blog/critical-vuln
96.
by mcpherrinm 1y ago
I’m the technical lead for the Let’s Encrypt SRE/infra team. So I spend a lot of time thinking about this. The salt here is deserved! JSON Web Signatures are a gnarly format, and the ACME API is pretty enthusiastic about being RESTful.
97.
by mcpherrinm 1y ago
I tested before they acknowledged or disabled the method (I was able to use a 3.2.2.4.14 validation the “normal” way)
98.
by mcpherrinm 1y ago
I couldn’t reproduce the attack with a pair of my own domains, so I think it might be even narrower in scope than the initial post suggests. But I suppose we will just have to wait to see what the CA says.
99.
by mcpherrinm 1y ago
CAA plus DNSSEC also provides significant defense against some types of attacks on domain validation.
100.
by mcpherrinm 1y ago
Must-staple has almost zero adoption. The engineering cost of supporting it for a feature that is nearly unused just isn’t there. We did consider it. As CAs prepare for post-quantum in the next few years, it will become even less practical
101.
by mcpherrinm 1y ago
The certificate remained unrevoked in OCSP until after SSL.com acknowledged the issue, so I don’t think the reporter was the one who had it revoked. It is also possible I was being served a stale/cached OCSP response.
102.
by mcpherrinm 1y ago
It would be possible to change, though that would be a pretty big change. Personally I think this is another good argument for short lived certificates and reducing reliance on revocation systems.
103.
by mcpherrinm 2y ago
There's no such thing as an ideal world, just the one we have. Let's Encrypt was founded with a goal of rapidly (within a few years) helping get the web to as close to 100% encrypted as we could. And we've succeeded. I don&#
104.
by mcpherrinm 2y ago
It makes the system more reliable and more secure for everyone. I think that's a big win. The root reason is that revocation is broken, and we need to do better to get the security properties we demand of the Web PKI.
105.
by mcpherrinm 2y ago
I'm on the team at Let's Encrypt that runs our CA, and would say I've spent a lot of time thinking about the tradeoffs here. Let's Encrypt has always self-imposed a 90 day limit, though of course with this ballot passing
106.
by mcpherrinm 2y ago
Firefox, Safari, and soon Android also support enforcing CT
107.
by mcpherrinm 2y ago
I can’t see freely available intermediates ever happening. The first three reasons I can think of are here, but there’s more I’m sure. 1. No way to enforce what the issued end-entity certificates look like, beyond name constraints. X509 is
108.
by mcpherrinm 2y ago
OpenSSF scorecard flags dependencies (including GitHub actions) which aren’t pinned by hash https://scorecard.dev/ https://github.com/ossf/scorecard/blob/main/docs/checks.md#p...
109.
by mcpherrinm 2y ago
I think the main reason is it allows for easier access to Tor hidden sides with a “regular” web browser. Consider a wifi network that exposed .onion domains via normal DNS, or a VPN, or other similar mechanisms. It’s not as good as Tor br
110.
by mcpherrinm 2y ago
I think Apple tests on "IPv6 Only" networks that have DNS64/NAT64 to reach v4 servers
111.
by mcpherrinm 2y ago
> That doesn't necessarily mean full CT support – they might just as well choose to completely distrust anything tagged SCTNotAfter, or to ignore it. That's what the blog post I linked in the top comment suggests is the "m
112.
by mcpherrinm 2y ago
The flipside of the same technical points is https://sslmate.com/blog/post/entrust_distrust_more_disrupti... where some non-browser clients don't handle this, or worse, handle it incorrectly.
113.
by mcpherrinm 2y ago
Really depends on who you ask. You still need v4 to be "globally reachable", but v6 is optional. AWS seems to finally be feeling the pinch of IPv4 exhaustion and is pushing v6 support everywhere now, and starting to charge for v4.
114.
by mcpherrinm 2y ago
Is there any mechanism to ensure you use "genuine" ink, or can you just dump whatever in?
115.
by mcpherrinm 2y ago
Right, any CA you add yourself that isn’t part of what Mozilla ships isn’t considered a publicly trusted CA.
116.
by mcpherrinm 2y ago
No. CT is only required for public CAs. You only need those browser policy settings if you’re using a public CA without CT.
117.
by mcpherrinm 2y ago
In any security setting, it’s usually good to have both controls and detection. CAA records help prevent unexpected issuance, but what if your DNS server is compromised? DNSSEC might help. Certificate Transparency provides a detection mecha
118.
by mcpherrinm 2y ago
.top is definitely a shady spot. They’re inexpensive and not very responsive to abuse reports - https://www.icann.org/uploads/compliance_notice/attachment/1... .xyz though I mostly associate with abc.xyz, the
119.
by mcpherrinm 2y ago
I fundamentally don't buy the argument that our products need to be shitty so that we can break them.
120.
by mcpherrinm 2y ago
It’s time to stop governments from hacking people’s phones, taking away their privacy? Users should have control and trust in their devices. If they can be remotely compromised, they cannot get that.

More ›