This is the
second half of my post on FERC’s new NOPR, which was released on July 16, 2015.
You can find the first half here.
I recommend you read the first post before you read this. Besides repeating the
not-so-surprising news that FERC intends to approve the v6 standards, the first
post discussed FERC’s request for comments on their proposal (not yet a
directive) that CIP be revised to provide protection for communications between
all control centers in the Bulk Electric System. This post discusses the
remaining issues that FERC is considering for new or revised standards. FERC is
asking for comments on all of these topics.
Protections for Remote Access
FERC says
they wish to have comments on “the value achieved if the CIP standards were to
require the incorporation of additional network segmentation controls,
connection monitoring, and session termination controls behind responsible
entity intermediate systems.” They base this on statements made by two of the
speakers at the April Technical Conference that suggested the need for further
protections.[i]
I didn’t realize that Intermediate Systems and Interactive Remote Access were
so poorly protected with the current wording, but I’ll defer to others who know
more than I do about this.
A New Supply Chain Security Standard?
FERC
surprised me – and I suspect a lot of others in the industry – with their
seemingly out-of-the-blue suggestion (Section E, starting on page 37) that
there should be a standard for security of the supply chain. I don’t believe
this means having armed guards accompanying trucks delivering transformers, but
rather – among other things - protection against the introduction of malicious
code at the “factory” level; that is, introducing malware into control system
software and firmware.
I’ve
certainly known for a while that some people were quite concerned about the
possibility that – say – all switches sold by vendor X would have embedded
malware that could be “woken up” with the touch of a button by some evil genius
in a secure mountain fortress overseas, and that this would lead to a
nationwide power outage. But I certainly hadn’t heard a lot of buzz from
Congress about this danger, and since the FERC Commissioners and staff always
seem to be paying close attention to what is being said in Congress, it was
surprising – indeed, refreshing – to see this concern come out of the blue. In
fact, FERC freely admits that Order 791 never mentioned supply chain risks at
all, so this issue is completely different from all the others discussed in the
NOPR, which otherwise all deal with concerns raised in 791.
What
surprises me even more is that it’s not at all clear how FERC and NERC – which
of course have no direct authority over hardware and software vendors – can
write and implement a standard that will result in big improvements in this
area. It will obviously have to be done indirectly, by say requiring that new vendor
contracts contain certain provisions. And that makes me wonder about any
antitrust implications of this effort.
In any case,
I do agree with FERC that this is an important concern, and if it can be
sufficiently addressed through a standard that applies to a group of customers,
not the vendors themselves, then it’s certainly worth examining in more depth.
Of course, this concern definitely needed to be addressed in a NOPR, not an
Order. However, I believe a separate NOPR would have been better, given that
this issue is so divorced from the others discussed in this document. I really
doubt FERC will be able to decide what it will do on this issue for quite a
while; I certainly hope they don’t hold up addressing all of the other issues
in the NOPR until this one can be addressed.[ii]
LERC
This
delightful acronym (EnergySec describes it as “Seuss-ian” in a recent
newsletter), of course, stands for Low impact External Routable Connectivity.
This concept is used (in CIP-003-6 Attachment 1) as a qualifier for how much
certain Low impact assets have to be protected, analogously to how External
Routable Connectivity serves as a qualifier for some Medium impact BES Cyber
Systems. I believe the v6 SDT invented a different phrase because they were
worried that, by using ERC in qualifying the Low assets, they might end up
having the auditors treat individual cyber assets at a Low asset differently
depending on whether or not they had ERC – and that would then lead to being
audited at the cyber asset level, which supposedly is strictly verboten for Low assets. But guess what, SDT? It seems the new term may
not have prevented that from happening after all….However, I’m getting ahead of
myself.
FERC
discusses LERC in Sections 68-70 on pages 43 and 44. They have an issue with
the first part of the definition: “Direct user-initiated interactive access or
a direct device-to-device connection to a low impact BES Cyber System(s) from a
Cyber Asset outside the asset containing those low impact BES Cyber System(s)
via a bidirectional routable protocol connection.”
FERC’s issue
is not really with the definition itself, but with the fact that they think the
word “Direct” isn’t being properly interpreted by NERC. They point in
particular to Reference Model 6 on page 36 of CIP-003-6, which purports to show
a situation where there is no LERC. In the diagram, an outside system connects
routably to a “Cyber Asset” (not a BCS) that is itself non-routably (serially)
connected to a BCS.
At first
glance, this doesn’t differ significantly from Reference Model 4, in which an
“IP/Serial Converter” is in the same logical position as the Cyber Asset in Model
6. However, in Model 4 it is stated that there is LERC, while in Model 6 it is
stated that there isn’t. Specifically, the description for Model 6 says “There
is a Layer 7 application layer break or the Cyber Asset requires authentication
and then establishes a new connection to the Low impact BES Cyber System.”
This, in the SDT’s opinion, separates LERC from non-LERC.
FERC states
in paragraph 70, “...we seek comment on the implementation of the ‘layer 7
application layer break’ contained in certain reference diagrams in the
Guidelines and Technical Basis section of proposed Reliability Standard
CIP-003-6. It appears that guidance provided in the
Guidelines and Technical Basis section of the proposed standard may conflict
with the plain reading of the term ‘direct.’”
To summarize
the above, it appears to me (and FERC could have been a little clearer, in my
opinion) that FERC wants NERC to provide explicit guidance on what “application
layer break” means and why it results in the connection no longer being
“direct”. If NERC doesn’t explain this well enough, it sounds like FERC will
order that the LERC definition be rewritten. Were that to happen, they should
probably order that the ERC definition be rewritten as well, since the best
discussion I’ve heard from NERC or the regions on ERC (by Morgan King of WECC.
See my recent post
on ERC) also relies heavily on the idea of an application layer break (Morgan
calls it a “protocol break”).
This might
sound like it’s a nice discussion about semantics, but there is quite an
important implication for NERC entities with Low impact assets. Remember that
the v5 and v6 SDTs have gone through contortions to make it clear that an
inventory of Low impact Cyber Assets isn’t required for compliance – any
requirements that apply to Lows are supposed to apply only at the asset level.[iii]
However, if the entity is going to prove that there is no LERC at a particular
Low asset – when there is clearly some routable connection going into the asset
– then they are potentially going to have to do at least part of what Mediums
and Highs have to do: identify any BCS and show that there is no LERC to any of
them.
I started to
write this section with my sympathies on NERC’s side of the argument; it
appeared to me at first glance that FERC was taking things too far. However, I
now see that the v6 SDT may have made a mistake by trying to, in cases where
there is an external routable connection coming into a Low asset, assert that
in some cases there is no LERC, whereas in others there is. It seems the only
way this can be demonstrated is by looking at the individual Cyber Assets, and
that will require some sort of inventory. It would probably be better if the
definition just said that if there is any routable connection coming into the
asset, there is LERC; if not, there isn’t LERC.
What can
NERC do to satisfy FERC now? Presumably a guidance document would be
sufficient, since the issue isn’t in the requirement itself, but in the
Guidance and Technical Basis section of CIP-003-6. This issue should not
require a new definition. But if NERC doesn’t provide guidance, or if they do
and FERC isn’t satisfied with what they provide, then FERC will probably order
a new definition be drafted. But note that, whatever happens, the clarification
should apply to ERC as well as to LERC, since the idea of a protocol break
applies to both definitions.[iv]
Transient Devices
FERC
discusses the new requirement CIP-010-2 R4 for Transient Devices in Section C
of the NOPR, which starts with paragraph 33 on page 20. They agree that the
requirement, which applies only to High and Medium impact BES Cyber Systems, is
good as far as it goes. However, they are concerned with the fact that it
doesn’t apply to Lows.
To
illustrate their concern, FERC says (page 26, paragraph 42) “For example,
malware inserted via a USB flash drive at a single Low Impact substation could
propagate through a network of many substations without encountering a single
security control under NERC’s proposal. In addition, we note that Low Impact
security controls do not provide for the use of mandatory
anti-malware/antivirus protections within the Low Impact facilities,
heightening the risk that malware or malicious code could propagate through
these systems without being detected.”
To discuss
the first sentence first, I wonder how many substations are connected like FERC
imagines – a lot of substations all on one routable network? If there is any
external connectivity in a substation, it is almost always with the control
center (which should always have good security controls in place). I’m not an
expert on this, but I really don’t think there are many networks where all the
substations are routably connected in a peer-to-peer fashion. So I tend to
agree with the SDT that the risk of a virus – carried in on a USB stick –
propagating like wildfire from one substation (or generating station) to
another is fairly minimal.
FERC’s
second sentence points out that CIP v5 doesn’t require anti-malware measures at
Lows, which FERC says heightens the risk. But I’d like to point out:
- Just because anti-malware isn’t mandated doesn’t mean it’s
not being used. Given the dangers, I doubt there are many NERC entities
that wouldn’t always have measures like antivirus deployed wherever
possible.
- For devices where it isn’t deployed, my guess is they mostly
are a.) not susceptible to normal malware because they don’t employ a
standard OS like Windows or Linux or b.) performing real-time operations
that might be hindered through antivirus software.
- If there really isn’t the widespread connectivity among
substations that FERC seems to think there is, the fact that CIP doesn’t
require anti-malware at Lows doesn’t really change anything. An infection
isn’t likely to spread beyond the substation regardless of whether
anti-malware is deployed or not.
FERC goes on
in paragraph 43 to request that NERC provide more justification for limiting
this requirement to High and Medium impact BCS, and says that if NERC still
can’t satisfy them, they will likely direct NERC to extend the requirement to
Low BCS. This might be quite a difficult requirement to comply with, since
substations are typically not manned. How do you prevent a contractor from
plugging in a USB stick if it hasn’t been approved by the owner of the
substation – since they will presumably already be granted the physical access
they need to accomplish what they were sent to do?
This is a
situation where the control, however beneficial, would be mis-applied. The
controls need to be applied to the employees and contractors visiting the
substation, through policies and training, as well as – in the contractors’
case – legal agreements that make clear what is expected regarding transient
devices. But there should not be device-level controls for Low impact assets. If
this really is an important issue, FERC should order NERC to make changes to CIP-004[v] so that
the training requirements apply to Lows (or a subset of those requirements),
not extend CIP-010 R4 to Low impact assets.
Here is Part III of this post.
Here is Part III of this post.
The views and opinions expressed here are my own and don’t
necessarily represent the views or opinions of Deloitte Advisory.
[i]
Of course, an “Intermediate System” is required of Medium and High impact
facilities to control interactive remote access to systems within the ESP. So
FERC seems to feel there could be more protection applied to IRA.
[ii]
However, see my next post, where I speculate whether FERC actually might want to move the enforceable date for
CIP v5 and v6 back from 4/1/16, and whether they’ll use a delay in approving v6
as a means of accomplishing that goal.
[iii]
The first draft of CIP v5, which was roundly voted down in December 2011,
contained a single requirement that applied to Lows: that default vendor
passwords needed to be changed. Since the only way to audit that would have
been for the entity to show they’d changed passwords on all of their Cyber
Assets, this would obviously have required an inventory of those Cyber Assets.
The reaction was so negative that the SDT made sure to remove this requirement
in the second draft and just left requirement CIP-003-5 R2, which requires the
entity to have four policies – until FERC said that wasn’t enough in Order 791.
[iv]
If NERC decides to take my advice and just say that whenever there is ERC into
a Low asset there is LERC, then this clarification would not involve the
protocol break concept – and it wouldn’t apply at all to ERC (which is
definitely a cyber asset-level concept, not an asset-level one).
[v]
CIP-004-6 R2.1 already references Transient Cyber Assets in the list of
training required, for Highs and Mediums. If this is so important, maybe there
should be a similar training requirement applicable to Lows, and also
applicable to contractors. But even though that wouldn’t be a device-level
requirement, it would also be very difficult to implement; I also don’t believe
the benefit from this approach would outweigh the costs required for
compliance.
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