Paul Ducklin talks to world-renowned cybersecurity professional Fraser Howard, Director of Analysis at SophosLabs, on this fascinating episode, recorded throughout our current Safety SOS Week 2022.
In relation to combating cybercrime, Fraser really is a “specialist in the whole lot”, and he additionally has the knack of explaining this difficult and treacherous topic in plain English.
[ROBOT VOICE: Sophos Security SOS]
PAUL DUCKLIN. Good day, everyone.
Welcome to the Sophos Safety SOS week.
Immediately’s matter is: Stopping cyber threats – cease them earlier than they cease you!
And our visitor as we speak is none apart from Mr. Fraser Howard, Director of Analysis at SophosLabs.
Now, these of you who’ve listened to SOS Week earlier than will know that I like to explain Fraser as a “specialist in the whole lot”, as a result of his data isn’t just broad, additionally it is extremely deep.
He ticks each cell within the spreadsheet, you would say.
So, Fraser, welcome again to the SOS Week.
I wished to begin by specializing in one thing that goes by the title of LOLBIN, which I consider is brief for “living-off-the-land binary”, which is jargon for software program that’s there already that the cooks love to make use of.
FRASER HOWARD. Precisely that.
DUCK. And the large drawback in the mean time appears to be that the almost certainly LOLBIN, or the almost certainly pre-installed program that the crooks will dine out on, for need of a greater phrase, is nothing apart from PowerShell, which is constructed into Home windows.
It’s obtainable on each model of Home windows as quickly as you put in it.
And it’s the medium of administration today for Home windows itself.
So how do you reside with out it?
FRASER. Precisely – identical to you described, from the attackers’ perspective, LOLBINs are good.
They both convey their very own knife to the battle, and their knife would possibly look very completely different to the whole lot else that’s on the system…
…or they use a knife that simply occurs to be current on the system within the first place.
And that’s advantageous to the attacker, for apparent causes.
Any safety software program gained’t see some model new, shiny, unknown software all of the sudden being run and utilized in a part of the assault.
However instruments like PowerShell are already there – that’s when the video games start when it comes to attempting to work out, “Is it one thing good, or is it one thing unhealthy?”
I want there was a one-line reply to how we detect malicious PowerShell versus benign, however truly it’s fairly a fancy scenario.
What precisely is the PowerShell course of doing itself?
On one finish of the spectrum, you would use know-how like, for instance, software management.
And as an admin, you would select: “PowerShell, you shouldn’t be allowed to run in my atmosphere.”
That’s sort of a panacea, when you like, and it could cease PowerShell being abused, however it could additionally break a lot of professional exercise, together with the core administration of most Home windows machines as we speak.
DUCK. OK, so software management is Sophos’s title for the flexibility to detect, and optionally to dam, software program that’s not malware, however {that a} well-informed administrator won’t need to assist of their atmosphere?
FRASER. Precisely.
And it’s not nearly admins and their selection of “Which software ought to my customers be allowed to make use of?”
It’s about fundamentals.
If you consider safety, what’s one of many issues that we’ve been telling individuals for the final 5 or 10 years?
“Patch!”
For those who’re an administrator and also you’re permitting anyone to make use of no matter software they need for his or her browser, that’s perhaps 5 to 10 completely different browsers that you need to patch.
Really, for admins, applied sciences like software management allow them to slim that risk floor.
DUCK. However PowerShell… some individuals say, “Oh, simply block PowerShell. Block all .PS1 information. Job accomplished.”
FRASER. It’s not fairly so simple as that!
DUCK. May a sysadmin handle with out PowerShell in a contemporary Home windows community?
FRASER. [PAUSE] No.
[LAUGHTER]
I imply, there are coverage choices that they might select to solely enable sure signed scripts, for instance, to be run.
However there’s an entire number of suggestions and methods that the attackers know that attempt to bypass these mechanisms as properly.
Among the older scripting engines… the most effective instance is Home windows Scripting Host – most individuals don’t understand it’s there.
It’s not the one-stop store for admin that PowerShell is, however WSCRIPT and CSCRIPT…
…these binaries, once more, are on each single Home windows field.
They’re much more possible to outright block, and so they get abused, once more by malware.
DUCK. So the Home windows Scripting Host consists of issues like JavaScript (not working in your browser, outdoors your browser), and good outdated Visible Primary Script?
FRASER. There’s an entire host of them.
DUCK. Now, Visible Primary script is discontinued by Microsoft, isn’t it?
Nevertheless it’s nonetheless supported and nonetheless very extensively used?
FRASER. It’s extremely popular with the Unhealthy Guys, sure.
And it’s not simply scripting engines.
I can’t bear in mind precisely what number of binaries are on among the fundamental LOLBIN lists which can be on the market.
With the proper mixture of switches, unexpectedly, a binary that you just would possibly use to handle, for instance, certificates regionally…
…truly can be utilized to obtain any content material from a distant server, and reserve it to disk regionally.
DUCK. Is that CERTUTIL.EXE?
FRASER. Sure, CERTUTIL, for instance.
DUCK. As a result of that can be used to do issues like calculate file hashes.
FRASER. It may very well be used to obtain, for instance, base64-encoded executable content material, reserve it regionally, and decode it.
After which that content material may very well be run – as a means of probably getting by your net gateways, for instance.
DUCK. And that will get even worse with PowerShell, doesn’t it?
As a result of you possibly can take a base64-encoded string and feed that into PowerShell because the enter script, and it’ll quietly decode it for you.
And you may even put in a command line choice, are you able to not, to say, “Hey, if the person mentioned ‘don’t enable scripts to execute from the command line’, ignore it – I want to override that”?
FRASER. You talked about .PS1 information.
That’s a bodily script file which may exist on disk.
Really, PowerShell is fairly adept at doing issues filelessly, so simply the command line itself can include everything of the PowerShell command.
DUCK. Now, my understanding is most so-called “fileless malware” does contain information, in all probability various information in its operation…
…however there will probably be a key level at which one thing you would possibly detect *solely exists in reminiscence*.
So, safety software program that’s solely in a position to monitor disk entry will miss out.
How do you cope with that sort of scenario, the place the crooks have gotten all this semi-suspicious stuff, after which they’ve disguised the actually harmful bit with this fileless, memory-only trick?
How do you cope with that?
FRASER. One of many methods we cope with that, significantly with reference to PowerShell, is Microsoft supplies an interface which supplies us visibility into the behaviour of PowerShell.
So AMSI is an interface which distributors, safety distributors, can use to get a peep into malware.
DUCK. AMSI is… Anti-Malware Scanning Interface?
FRASER. Precisely.
It provides us a window into the behaviour of PowerShell at any cut-off date.
So, because it may be doing issues filelessly… any conventional interception factors that are on the lookout for information on disk, they gained’t be coming into play.
However the behaviour of PowerShell itself will generate exercise, when you like, inside the AMSI interface, which supplies us the flexibility to recognise and block sure forms of malicious PowerShell exercise.
The opposite factor is that, though “fileless” is seen as a little bit of a panacea for the unhealthy guys…
…truly, one of many issues that almost all attackers are after in some unspecified time in the future is what we name persistence.
OK, they’ve received some code working on the machine… however what occurs if that machine is restarted?
And so their fileless malware sometimes will search to have add some stage of persistence.
So, many of the fileless assaults that we’ve seen truly interact, sometimes with the Home windows Registry – they use the registry as a means of reaching persistence.
Usually, they put some form of BLOB [binary large object] of information within the registry, and modify some registry keys such that such that when that machine is restarted, that BLOB is decoded and malicious behaviour carries on once more.
Immediately’s merchandise are all about an entire vary of applied sciences, from easy, proper by to fairly terribly advanced.
DUCK. That additionally helps to clarify why individuals take information which can be kind-of the precursors of malware, however not overtly malicious themselves, add them to an internet service like, say, Virus Complete…
…and go, “Hey, no one detects this. All safety merchandise are ineffective.”
Nevertheless it doesn’t imply that file can spring into life and begin doing unhealthy stuff with out getting stopped…
FRASER. That’s an excellent level.
I feel it’s one thing the safety trade has tried… however the truth that we nonetheless speak about it – we’ve in all probability didn’t get this level throughout:
What’s safety?
What will we truly imply?
What does defending somebody towards a risk sometimes imply?
Most individuals have a tendency to consider it like this… OK, they’ve a risk; they need a file that’s “the risk”; and so they need to see if that file will get detected.
However that individual assault… let’s suppose it’s a bot.
There may be 10,000 of these information *each single day*, because the unhealthy guys flip their deal with and churn out a lot of completely different replicas which can be primarily all the identical primary factor.
And so the truth that 1, or 10, or 100 of these information will get detected…
…it doesn’t actually let you know very a lot about how properly a product would possibly defend towards that risk.
DUCK. “Bot” means software program robotic?.
Primarily, that’s one thing that sits in your pc repeatedly, calling residence or polling some random server?
FRASER. Precisely.
DUCK. That server could change from day after day… and the bot will regularly obtain an inventory of directions, comparable to “Right here’s an inventory of e-mail addresses to spam.”
Subsequent, it may very well be, “Here’s a listing of file extensions I need you to scramble”, or it may very well be “Activate the keylogger”?
FRASER. Precisely.
DUCK. Or “Take a screenshot proper now, they’re within the banking app”.
It’s primarily an lively backdoor…
FRASER. It *is* a backdoor, sure.
And we spoke about backdoors 20 years in the past… I bear in mind doing buyer shows 20 years in the past, speaking about backdoors.
DUCK. “Again Orifice”, when you bear in mind…
FRASER. Sure, sure!
We had been attempting to persuade clients that, truly, a whole lot of the backdoors on the market had been extra necessary than the high-profile malware of the day.
What you don’t need to get contaminated with are the backdoors, which permit some miscreant someplace the flexibility to regulate your machine and do unhealthy stuff, comparable to take a look by your file system, or modify information in your system.
That’s a much more scary risk than, for instance, a self-replicating worm that simply spreads from pc to pc.
That may get the press, and it’d trigger issues in and in and of itself…
…however, truly, any person gaining access to your system is arguably a a lot greater risk certainly.
DUCK. And considering again to Again Orifice in… what was it 1999? 2000?
That famously it listened on port 13337, didn’t it?
FRASER. You’ve received a great reminiscence [LAUGHS]… sure, “elite”!
DUCK. And as quickly as individuals began getting onto DSL connections at residence, and having a house router, Again Orifice was ineffective as a result of inbound connections didn’t work.
And so individuals thought, “Oh, properly, backdoors depend on inbound community connections – I’m protected by my ISP by default, so I don’t have to fret about it.”
However as we speak’s zombies, as we speak’s bots – they name residence utilizing some sort of encrypted or secretive channel, and so they *obtain* the directions…
FRASER. And since it’s on HTTPS, they principally cover that community exercise amongst the million-and-one different net packets that exit each minute on most residence connections.
DUCK. In order that’s one more reason why you need defence-in-depth or layered safety?
FRASER. Sure.
DUCK. Clearly, new information – you need to look at them; you don’t need to miss malware that you would have detected.
However the file may very well be harmless in the mean time, and it might transform rogue after it’s loaded; after it’s manipulated itself in reminiscence; after it’s known as out and downloaded stuff…
FRASER. And so, to get again to the unique level: how we measure safety merchandise as we speak is extra advanced than it ever has been.
DUCK. As a result of some individuals nonetheless have the concept, properly, when you actually need to take a look at a product, you simply get a large bucket stuffed with malware, all in information…
FRASER. Commmonly known as “a zoo”.
DUCK. …and you place that on a server in isolation someplace.
Then you definitely scan it with a static scanner, and also you learn the way many it detects, and that tells you the way the product behaves.
The “Virus Complete” strategy.
However that: [A] will are likely to underestimate good merchandise, and [B] would possibly overestimate unhealthy merchandise.
FRASER. Or merchandise that specialize in detecting information solely, for the aim of primarily trying good in these form of zoo-based assessments.
That doesn’t translate to a product in the actual world that may truly present good ranges of safety!
In actuality, we block information… in fact we do – the file remains to be a vital forex, when you like, when it comes to safety.
However there’s a lot of different issues, for instance just like the AMSI interface that lets us block malicious PowerShell exercise, and a program’s behaviour itself.
So, inside our product, the behavioural engine appears on the behaviour of processes, community, visitors, registry exercise…
…and that mixed image lets us spot probably malicious behaviour for the aim of blocking not essentially a particular household, or perhaps a specific sort of sort of risk, however simply *malicious exercise*.
If there are specific forms of behaviour that we will decide are simply outright malicious, we are going to typically attempt to block that.
We will block a sure kind of malicious behaviour as we speak, after which a risk household that has not even but been written – in three months time, it’d use that very same behaviour, and we are going to proactively detect it.
In order that’s the Holy Grail of what we do: proactive safety.
The flexibility for us to jot down one thing as we speak that sooner or later will efficiently block malicious behaviour.
DUCK. I suppose a great instance of that, to return to what we talked about earlier than, is CERTUTIL.EXE – that certificates validation utility.
You may be utilizing that in your personal scripts, in your personal sysadministration instruments, but there are some behaviours that you wouldn’t count on, though that program will be made to do these issues.
They might stand out.
FRASER. They might stand out, precisely.
DUCK. So you possibly can’t say, “This system is unhealthy”, however in some unspecified time in the future in its behaviour you possibly can go, “Aha, now it’s gone too far!”
FRASER. And that touches on one other attention-grabbing side of as we speak’s panorama.
Traditionally, EVIL.EXE runs; we’d detect the file; we’d detect some malicious behaviour; we clear it out of your system.
You spoke about LOLBINs… clearly, after we detect PowerShell doing one thing malicious, we don’t take away POWERSHELL.EXE from that system.
DUCK. “Ooh, I discovered Home windows doing one thing unhealthy – wipe the entire system!”
[LAUGHTER]
FRASER. We principally block that course of; we cease that course of doing what it was about to do; and we terminate it.
However PowerShell nonetheless exists on the bodily system.
Really, as we speak’s attackers are very completely different from yesterday’s attackers as properly.
Immediately’s attackers are all about having a aim; having a goal.
The outdated mannequin was extra spray-and-pray, when you like.
If any person blocks the assault… unhealthy luck, they offer up – there’s no human presence there.
If the assault works, information is stolen, a machine turns into compromised, no matter it occurs to be, but when the assault was blocked, nothing else occurs on the system.
In as we speak’s assaults, there truly is way more of a human aspect.
So, sometimes, in a whole lot of assaults we see as we speak – that is typified by a lot of the ransomware assaults, the place the crooks are particularly attempting to focus on sure organisations with their ransomware creations…
…when one thing is blocked, they fight once more, and so they carry on retrying.
As we’re blocking stuff, and blocking several types of malicious behaviour, there’s one thing behind the scenes; some *particular person* behind the scenes; some risk group behind the scenes, retrying.
DUCK. So 10 or 15 years in the past, it was, “Oh, we discovered this brand-new, beforehand unknown Phrase malware. We’ve deleted the file and cleaned it up, and we wrote it within the log”.
And everybody goes into the assembly, and ticks it off, and pats one another on the again, “Nice! Job accomplished! Prepared for subsequent month.”
FRASER. Now, it’s very completely different.
DUCK. Immediately, *that wasn’t the assault*.
FRASER. No!
DUCK. That was only a precusor, an “I’m wondering what model of smoke detectors they use?” sort of take a look at.
FRASER. Precisely.
DUCK. And so they’re not planning on utilizing that malware.
They’re simply attempting to guess precisely what safety have you ever received?
What’s turned on; which directories are included; which directories are excluded out of your scanning; what ambient settings have you ever received?
FRASER. And what we speak about as we speak is lively adversaries.
Energetic adversaries… they get a lot of press.
That’s the idea of the entire MITRE ATT&CK framework – that’s is actually a bible, a dictionary, when you like, of combos of techniques.
The techniques are the verticals; the horizontals are the methods.
I feel there are 14 techniques however I don’t know what number of methods… a whole bunch?
DUCK. It may be a bit dizzying, that MITRE grid!
FRASER. It’s primarily a dictionary of the several types of issues, the several types of approach, that may very well be used on a system for good or unhealthy, primarily.
Nevertheless it’s primarily aligned to attackers and lively adversaries.
For those who like, it’s a taxonomy of what an lively adversary would possibly do when on the system.
DUCK. Proper, as a result of within the outdated days (you and I’ll bear in mind this, as a result of we each frolicked writing complete malware descriptions, the sort of issues that had been crucial 15 or 20 years in the past – you had been speaking about EVIL.EXE)…
…as a result of most threats again then had been viruses, in different phrases they unfold themselves and so they had been self-contained.
As soon as we had it…
FRASER. …you would doc, A-to-Z, precisely what it did on the system.
DUCK. So a whole lot of malware again in these days, when you take a look at how they hid themselves; how they went into reminiscence; polymorphism; all that stuff – a whole lot of them had been much more sophisticated to analyse that stuff as we speak.
However when you knew the way it labored, you knew what each era may appear to be, and you would write a whole description.
FRASER. Sure.
DUCK. Now, you simply can’t do this.
“Properly, this malware downloads another malware.”
What malware?
“I don’t know.”
FRASER. For instance, contemplate a easy loader: it runs; it periodically connects out.
The attacker has the flexibility to fireplace in some form of encoded BLOB – for instance, let’s suppose it’s a DLL, a dynamic hyperlink library, a module… primarily, some executable code.
So, “What does that risk do?”
Properly, it relies upon precisely and completely on what the attacker sends down the wire.
DUCK. And that might change day-to-day.
It might change by supply IP: “Are you in Germany? Are you in Sweden? Are you in Britain?”
FRASER. Oh, sure we see that very often.
DUCK. It might additionally say, “Hey, you already related, so we’ll feed you NOTEPAD or some harmless file subsequent time.”
FRASER. Sure.
The attackers sometimes can have methods they use to attempt to spot when it’s us [i.e. SophosLabs] attempting to run their creation.
In order that they don’t feed us what may be the final word payload.
They don’t need us to see the payload – they solely need victims to see that payload.
Typically issues simply exit quietly; generally they only run CALC, or NOTEPAD, or one thing clearly foolish; generally we’d get a impolite message popping up.
However sometimes they’ll attempt to preserve again the final word payload, and reserve that for his or her victims.
DUCK. And that additionally means…
…I glibly used the phrase “polymorphism” earlier; that was quite common in viruses again within the day, the place each time the virus copied itself to a brand new file it could principally permute its code, typically in a really sophisticated means, even rewriting its personal algorithm.
However you would get the engine that did the scrambling.
FRASER. Sure.
DUCK. Now, the crooks preserve that to themselves.
FRASER. That’s on a server some other place.
DUCK. And so they’re turning the deal with within the background.
FRASER. Sure.
DUCK. And likewise you talked about loaders – individuals could have heard of issues like BuerLoader, BazaarLoader, they’re form of well-known “model names”…
..in some instances, there are gangs of crooks, and that’s all they do.
They don’t write the malware that comes subsequent.
They only say, “What would you want us to load? Give us the URL and we’ll inject it for you.”
FRASER. The unique bot operators from 15 or 20 years in the past – how did they generate profits?
They compromised networks of machines – that’s primarily what a botnet is, a lot of machines beneath their command – after which they might principally lease out that “community”.
It may very well be for distributed denial of service – get all of those contaminated machines to hit one net server for instance, and take out that net server.
It may very well be fairly generally for spam, as you’ve already talked about.
And so the pure evolution of that, in some sense, is as we speak’s loader.
If any person has a system contaminated with a loader, and that loader is looking residence, you primarily have a bot.
You might have the flexibility to run stuff on that machine…
…so, identical to you say, these cybercriminals don’t should be involved with what the final word payload is.
Is it ransomware?
Is it information theft?
They’ve a car… and ransomware is nearly the ultimate payout.
“We’ve accomplished the whole lot we wished to do.” (Or we failed in the whole lot else we had been hoping to do.)
“Let’s simply strive ransomware…”
DUCK. “We’ve logged all of the passwords now, there are not any extra to get.” [LAUGHS]
FRASER. There’s nowhere else to go!
DUCK. “We’ve stolen all the information.”
FRASER. Precisely… the ultimate cash-out is ransomware!
At that time, the person is conscious, and the directors conscious, there’s information loss.
So, as we speak’s loader is nearly an extension of, an evolution of, yesterday’s bot.
DUCK. Fraser, I’m aware of time…
So, given that you just’ve painted an image that clearly requires full-time work, full-time understanding – you’re an professional researcher, you’ve been doing this for years.
Not everyone can provide up their day job in IT or sysadministration to have *one other* day job to be such as you within the organisation.
For those who needed to give three easy suggestions for what you need to do (or what you shouldn’t do) as we speak to cope with what’s a extra sophisticated, extra fragmented means of attacking from the crooks – one that offers us many extra planes on which we have to defend…
… what would these three issues be?
FRASER. That’s a troublesome query.
I feel the primary one must be: having consciousness and visibility into your organisation.
It sounds easy, however we very often see assaults the place the start line of an assault was an unprotected field.
So, you will have an organisation….
…they’ve a beautiful IT coverage; they’ve merchandise deployed throughout that community, correctly configured; they may have a crew of individuals which can be waiting for all of the little sensors, and all the information getting back from these merchandise.
However they’ve a site controller that was unprotected, and the unhealthy guys managed to get onto that.
After which, inside the entire MITRE ATT&CK framework, there’s one approach known as lateral motion…
…as soon as the attackes are on a field, they may proceed to attempt to laterally transfer from there throughout the organisation.
And that preliminary sort of foothold provides them some extent from which they’ll do this.
So, visibility is the primary level.
DUCK. You additionally should know what you don’t know!
FRASER. Sure – having visibility into all of the units in your community.
Quantity two is: configuration.
This can be a little bit of a thorny one, as a result of nobody likes to speak about insurance policies and configuration – it’s frankly fairly boring.
DUCK. It’s sort of necessary, although!
FRASER. Completely essential.
DUCK. “For those who can’t measure it, you possibly can’t handle it,” because the outdated saying goes.
FRASER. I feel my one suggestion for that might be: if in any respect doable, use the really useful defaults.
As quickly as you deviate away from really useful defaults, you’re sometimes both turning stuff off (unhealthy!), otherwise you’re excluding sure issues.
DUCK. Sure.
FRASER. For instance, excluding a selected folder.
Now, that may be completely acceptable – you may need some customized software in it, some customized database software the place you say, “I don’t need to scan information inside this specific folder.”
It’s not fairly so good when you’re excluding, for instance, the Home windows folder!
DUCK. “Exclude C:*.* and all subdirectories.” [LAUGHS]
FRASER. It’s.
DUCK. You add one, you add one other, and you then don’t go and evaluate it…
…you find yourself the place you principally have all of the doorways and all of the home windows propped open.
FRASER. It’s a bit like a firewall.
You block the whole lot; you poke a number of holes: high quality.
You retain on poking holes for subsequent three years, and earlier than the place you’re…
…you will have Swiss cheese as your firewall.
[LAUGHTER]
It’s not going to work!
So, configuration is de facto necessary, and, if in any respect doable follow the defaults.
DUCK. Sure.
FRASER. Keep on with defaults, as a result of… these really useful defaults – they’re really useful for a cause!
Inside our personal merchandise, for instance, whenever you deviate from defaults, very often you’ll get a pink bar warning that you just’re principally disabling safety.
DUCK. For those who’re going to go off-piste, ensure you actually meant to!
FRASER. Ensure you have good visibility.
And I suppose the third level, then, is: acknowledge the ability set required.
DUCK. Don’t be afraid to name for assist?
FRASER. Sure: Don’t be afraid to name for assist!
Safety is advanced.
We like to consider it’s easy: “What three issues can we do? What easy issues can we do?”
Really, the truth is that as we speak’s safety could be very sophisticated.
Merchandise would possibly attempt to package deal that up in a reasonably easy means, and supply good ranges of safety and good ranges of visibility into several types of behaviour taking place in a community.
However when you don’t have the ability set, or the useful resource for that matter, to work although the occasions which can be coming in and hitting your dashboard…
…discover somebody that does!
For instance, utilizing a managed service could make a large distinction to your safety, and it will possibly simply take away that headache.
DUCK. That’s not an admission of defeat, is it?
You’re not saying, “Oh, I can’t do it myself.”
FRASER. We’re speaking 24 x 7 x 365.
So, for somebody to try this in-house is a large enterprise.
And we’re additionally speaking about advanced information – and we spoke about lively adversaries, and that form of assault.
We all know the Unhealthy Guys, even after we block stuff, will proceed to retry: they’ll change issues up.
crew which can be taking a look at that information will recognise that kind of behaviour, and they won’t solely know that one thing’s being blocked, these individuals can even suppose, “OK, there’s any person repeatedly attempting to get in by that door.”
That’s fairly a helpful indicator to them, and so they’ll take motion, and so they’ll resolve the assault.
[PAUSE]
Three fairly good items of recommendation there!
DUCK. Glorious, Fraser!
Thanks a lot, and thanks for sharing your expertise and your experience with us.
To everyone who’s listening, thanks a lot.
And it stays now just for me to say: “Till subsequent time, keep safe.”
[MORSE CODE]
