ICANN CTO: no reason to delay KSK rollover
ICANN’s board of directors will be advised to go ahead with a key security change at the DNS root — “the so-called KSK rollover” — this October, according to the organization’s CTO.
“We don’t see any reason to postpone again,” David Conrad told DI on Monday.
If it does go ahead as planned, the rollover will see ICANN change the key-signing key that acts as the trust anchor for the whole DNSSEC-using internet, for the first time since DNSSEC came online in 2010.
It’s been delayed since last October after it emerged that misconfigurations elsewhere in the DNS cloud could see potentially millions of internet users see glitches when the key is rolled.
Ever since then, ICANN and others have been trying to figure out how many people could be adversely affected by the change, and to reduce that number to the greatest extent possible.
The impact has been tricky to estimate due to patchy data.
While it’s been possible to determine a number of resolvers — about 8,000 — that definitely are poorly configured, that only represents a subset of the total number. It’s also been hard to map that to endpoints due to “resolvers behind resolvers behind resolvers”, Conrad said.
“The problem here is that it’s sort of a subjective evaluation,” he said. “We can’t rely on the data were seeing. We’re seeing the resolvers but we’re not seeing the users behind the resolvers.”
Some say that the roll is still too risky to carry out without better visibility into the potential impact, but others say that more delays would lead to more networks and devices becoming DNSSEC-compatible, potentially leading to even greater problems after the eventual rollover.
ICANN knows of about 8,000 resolver IP addresses that are likely to stop working properly after the rollover, because they only support the current KSK, but that’s only counting resolvers that automatically report their status to the root using a relatively new internet standard. There’s a blind spot concerning resolvers that do not have that feature turned on.
ICANN has also had difficulty reaching out to the network operators behind these resolvers, with good contact information apparently only available for about a quarter of the affected IP addresses, Conrad said.
Right now, the best data available suggests that 0.05% of the internet’s population could see access issues after the October 11 rollover, according to Conrad.
That’s about two million people, but it’s 10 times fewer people than the 0.5% acceptable collateral damage threshold outlined in ICANN’s rollover plan.
The 0.05% number comes from research by APNIC, which used Google’s advertising system to place “zero-pixel ads” to check whether individual user endpoints were using compatible resolvers or not.
If problems do emerge October 11 the temporary solution is apparently quite quick to implement — network operators can simply turn off DNSSEC, assuming they know that’s what they’re supposed to do.
But still, if a million or two internet users could have their day ruined by the rollover, why do it at all?
It’s not as if the KSK is in any danger of being cracked any time soon. Conrad explained that a successful brute-force attack on the 2048-bit RSA key would take longer than the lifetime of the universe using current technology.
Rather, the practice of rolling the key every five years is to get network operators and developers accustomed to the idea that the KSK is not a permanent fixture that can be hard-coded into their systems, Conrad said.
It’s a problem comparable to new gTLD name collisions or the Y2K problem, instances where developers respectively hard-coded assumptions about valid TLDs or the century into their software.
ICANN has already been reaching out to the managers of open-source projects on repositories such as Github that have been seen to hard-code the current KSK into their software, Conrad said.
Separately, Wes Hardaker at the University of Southern California Information Sciences Institute discovered that a popular VPN client was misconfigured. Outreach to the developer saw the problem fixed, reducing the number of users who will be affected by the roll.
“What we’re trying to avoid is having these keys hardwired into firmware, so that that it would never be changeable,” he said. “The idea is if you exercise the infrastructure frequently enough, people will know the that the key is not permanent configuration, it’s not something embedded in concrete.”
One change that ICANN may want to make in future is to change the algorithm used to generate the KSK.
Right now it’s using RSA, but Conrad said it has downsides such as rather large signature size, which leads to heavier DNSSEC traffic. By switching to elliptical curve cryptography, signatures could be reduced by “orders of magnitude”, leading to a more efficient and slimline DNS infrastructure, Conrad said.
Last week, ICANN’s Root Server Stability Advisory Committee issued an advisory (pdf) that essentially gave ICANN the all-clear to go ahead with the roll.
The influential Security and Stability Advisory Committee has yet to issue its own advisory, however, despite being asked to do so by August 10.
Could SSAC be more cautious in its advice? We’ll have to wait and see, but perhaps not too long; the current plan is for the ICANN board to consider whether to go ahead with the roll during its three-day Brussels retreat, which starts September 14.
Is the .home new gTLD doomed? ICANN poses study of security risks
ICANN has set up a study into whether certain applied-for new gTLD strings pose a security risk to the internet, admitting that some gTLDs may be rejected as a result.
Its board of directors on Saturday approved new research into the risk of new gTLD clashes with “internal name certificates”, saying that the results could kill off some gTLD applications.
In its rationale, the board stated:
it is possible that study might uncover risks that result in the requirement to place special safeguards for gTLDs that have conflicts. It is also possible that some new gTLDs may not be eligible for delegation.
Internal name certificates are the same digital certificates used in secure, web-based SSL transactions, but assigned to domain names in private, non-standard namespaces.
Many companies have long used non-existent TLDs such as .corp, .mail and .home on their private networks and quite often they obtain SSL certs from the usual certificate authorities in order to enable encryption between corporate resources and their internal users.
The problem is that browsers and other applications on laptops and other mobile devices can attempt to access these private namespaces from anywhere, not only from the local network.
If ICANN should set these TLD strings live in the authoritative DNS root, registrants of clashing domain names might be able to hijack traffic intended for secure resources and, for example, steal passwords.
That’s obviously a worry, but it’s one that did not occur to ICANN’s Security and Stability Advisory Committee until late last year, when it immediately sought out the help of the CA/Browser Forum.
It turned out the the CA/Browser forum, an alliance of certificate authorities and browser makers, was already on the case. It has put in new rules that state certificates issued to private TLDs that match new gTLDs will be revoked 120 days after ICANN signs a contract with the new gTLD registry.
But it’s still not entirely clear whether this will sufficiently mitigate risk. Not every CA is a member of the Forum, and some enterprises might find 120 day revocation windows challenging to work with.
Verisign recently highlight the internal certificate problem, along with many other potential risks, in an open letter to ICANN.
But both ICANN CEO Fadi Chehade and the chair of SSAC, Patrick Falstrom, have said that the potential security problems are already being addressed and not a reason to delay new gTLDs.
The latest board resolution appears to modify that position.
The board has now asked CEO Fadi Chehade and SSAC to “consider the potential security impacts of applied-for new-gTLD strings in relation to this usage.”
The Root Server Stability Advisory Committee and the CA/Browser Forum will also be tapped for data.
While the study will, one assumes, not be limited to any specific applied-for gTLD strings, it’s well known that some strings are more risky than others.
The root server operators already receive vast amounts of erroneous DNS traffic looking for .home and .corp, for example. If any gTLD applications are at risk, it’s those.
There are 10 remaining applications for .home and five for .corp.
ICANN expects 400+ gTLD applications
If you’ve been wondering how many new gTLDs could be launching under the new streamlined ICANN approval process, ICANN has provided a partial answer.
According to a report into server load by the Root Server System Advisory Committee “demand in the initial round will be (continue reading)
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