Fintechs and Security – Part Two

Threat and Vulnerability Management (TVM) – Application Security

This part covers some high-level guider points related to the design of the application security side of TVM (Threat and Vulnerability Management), and the more common pitfalls that plague lots of organisations, not just fintechs. I won’t be covering different tools in the SAST or DAST space apart from one known-good. There are some decent SAST tools out there but none really stand out. The market is ever-changing. When i ask vendors to explain what they mean by [new acronym] what usually results is nothing, or a blast of obfuscation. So I’m not here to talk about specific vendor offerings, especially as the SAST challenge is so hard to get even close to right.

With vulnerability management in general, ${VENDOR} has succeeded in fouling the waters by claiming to be able to automate vulnerability management. This is nonsense. Vulnerability assessment can to some limited degree be automated with decent results, but vulnerability management cannot be automated.

The vulnerability management cycle has also been made more complicated by GRC folk who will present a diagram representing a cycle with 100 steps, when really its just assess –> deduce risk –> treat risk –> GOTO 1. The process is endless, and in the beginning it will be painful, but if handled without redundant theory, acronyms-for-the-sake-of-acronyms-for-the-same-concept-that-already-has-lots-of-acronyms, rebadging older concepts with a new name to make them seem revolutionary, or other common obfuscation techniques, it can be easily integrated as an operational process fairly quickly.

The Dawn Of Application Security

If you go back to the heady days of the late 90s, application security was a thing, it just wasn’t called “application security”. It was called penetration testing. Around the early 2000s, firewall configurations improved to the extent that in a pen test, you would only “see” port 80 and/or 443 exposing a web service on Apache, Internet Information Server, or iPlanet (those were the days – buffer overflow nirvana). So with other attack channels being closed from the perimeter perspective, more scrutiny was given to web-based services.

Attackers realised you can subvert user input by intercepting it with a proxy, modifying some fields, perhaps inject some SQL or HTML, and see output that perhaps you wouldn’t expect to see as part of the business goals of the online service.

At this point the “application security” world was formed and vulnerabilities were classified and given new names. The OWASP Top Ten was born, and the world has never been the same since.

SAST/DAST

More acronyms have been invented by ${VENDOR} since the early early pre-holocene days of appsec, supposedly representing “brand new” concepts such as SAST (Static Application Security Testing) and DAST (Dynamic Application Security Testing), which is the new equivalent of white box and black box testing respectively. The basic difference is about access to the source code. SAST is source code testing while DAST is an approach that will involve testing for OWASP type vulnerabilities while the software is running and accepting client connection requests.

The SAST scene is one that has been adopted by fintechs in more recent times. If you go back 15 years, you would struggle to find any real commercial interest in doing SAST – so if anyone ever tells you they have “20” or even “10” years of SAST experience, suggest they improve their creativity skills. The general feeling, not unjustified, was that for a large, complex application, assessing thousands of lines of source code at a vital organ/day couldn’t be justified.

SAST is more of a common requirement these days. Why is that? The rise of fintechs, whose business is solely about generation of applications, is one side of it, and fintechs can (and do) go bust if they suffer a breach. Also – ${VENDOR}s have responded to the changing Appsec landscape by offering “solutions”. To be fair, the offerings ARE better than 10 years ago, but it wouldn’t take much to better those Hello World scripts. No but seriously, SAST assessment tools are raved about by Gartner and other independent sources, and they ARE better than offerings from the Victorian era, but only in certain refined scenarios and with certain programming languages.

If it was possible to be able to comprehensively assess lots of source code for vulnerability and get accurate results, then theoretically DAST would be harder to justify as a business undertaking. But as it is, SAST + DAST, despite the extensive resources required to do this effectively, can be justified in some cases. In other cases it can be perfectly fine to just go with DAST. It’s unlikely ever going to be ok to just go with SAST because of the scale of the task with complex apps.

Another point here – i see some fintechs using more than one SAST tool, from different vendors. There’s usually not much to gain from this. Some tools are better with some programming languages than others, but there is nothing cast in stone or any kind of majority-view here. The costs of going with multiple vendors is likely going to be harder and harder to justify as time goes on.

Does Automated Vulnerability Assessment Help?

The problem of appsec is still too complex for decent returns from automation. Anyone who has ever done any manual testing for issues such as XSS knows the vast myriad of ways in which such issues can be manifested. The blackbox/blind/DAST scene is still not more than Burp, Dirbuster, but even then its mostly still manual testing with proxies. Don’t expect to cover all OWASP top 10 issues for a complex application that presents an admin plus a user interface, even in a two-week engagement with four analysts.

My preferred approach is still Fred Flinstone’y, but since the automation just isn’t there yet, maybe its the best approach? This needs to happen when an application is still in the conceptual white board architecture design phase, not a fully grown [insert Hipster-given-name], and it goes something like this: white board, application architect – zero in on the areas where data flows involve transactions with untrusted networks or users. Crpyto/key management is another area to zoom in on.

Web Application Firewall

The best thing about WAFs, is they only allow propagation of the most dangerous attacks. But seriously, WAF can help, and in some respects, given the above-mentioned challenges of automating code testing, you need all the help you can get, but you need to spend time teaching the WAF about your expected URL patterns and tuning it – this can be costly. A “dumb” default-configured WAF can probably catch drive-by type issues for public disclosed vulnerabilities as long as you keep it updated. A lot depends on your risk profile, but note that you don’t need a security engineer to install a WAF and leave it in default config. Pretty much anyone can do this. You _do_ need an experienced security engineer or two to properly understand an application and configure a WAF accordingly.

Python and Ruby – Web Application Frameworks

Web application frameworks such as Ruby on Rails (RoR) and Django are in common usage in fintechs, and are at least in some cases, developed with security in mind in that they do offer developers features that are on by default. For example, with Django, if you design a HTML form for user input, the server side will have been automagically configured with the validation on the server side, depending on the model field type. So an email address will be validated client and server-side as an email address. Most OWASP issues are the result of failures to validate user input on the server side.

Note also though that with Django you can still disable HTML tag filtering of user input with a “| safe” in the template. So it’s dangerous to assume that all user input is sanitised.

In Django Templates you will also see a CSRF token as a hidden form field if you include a Form object in your template.

The point here is – the root of all evil in appsec is server-side validation, and much of your server-side validation effort in development will be covered by default if you go with RoR or Django. That is not the end of the story though with appsec and Django/RoR apps. Vulnerability of the host OS and applications can be problematic, and it’s far from the case that use of either Django or RoR as a dev framework eliminates the need for DAST/SAST. However the effort will be significantly reduced as compared to the C/Java/PHP cases.

Wrap-up

Overall i don’t want to too take much time bleating about this topic because the take away is clear – you CAN take steps to address application security assessment automation and include the testing as part of your CI/CD pipeline, but don’t expect to catch all vulnerabilities or even half of what is likely an endless list.

Expect that you will be compromised and plan for it – this is cheaper than spending zillions (e.g. by going with multiple SAST tools as i’ve seen plenty of times) on solving an unsolvable problem – just don’t let an incident result in a costly breach. This is the purpose of security architecture and engineering. It’s more to deal with the consequences of an initial exploit of an application security fail, than to eliminate vulnerability.

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Fintechs and Security – Part One

Recruiting and Interviews

In the prologue of this four-stage process, I set the scene for what may come to pass in my attempt to relate my experiences with fintechs, based on what i am hearing on the street and what i’ve seen myself. In this next instalment, i look at how fintechs are approaching the hiring conundrum when it comes to hiring security specialists, and how, based on typical requirements, things could maybe be improved.

The most common fintech setup is one of public-cloud (AWS, Azure, GCP, etc), They’re developing, or have developed, software for deployment in cloud, with a mobile/web front end. They use devops tools to deploy code, manage and scale (e.g. Kubernetes), collaborate (Git variants) and manage infrastructure (Ansible, Terraform, etc), perhaps they do some SAST. Sometimes they even have different Virtual Private Clouds (VPCs) for different levels of code maturity, one for testing, and one for management. And third party connections with APIs are not uncommon.

Common Pitfalls

  • Fintechs adopt the stance: “we don’t need outside help because we have hipsters. They use acronyms and seem quite confident, and they’re telling me they can handle it”. While not impossible that this can work – its unlikely that a few devops peeps can give a fintech the help they need – this will become apparent later.
  • Using devops staff to interview security engineers. More on this problem later.
  • Testing security engineers with a list of pre-prepared questions. This is unlikely to not end in tears for the fintech. Security is too wide and deep an area for this approach. Fintechs will be rejecting a lot of good candidates by doing this. Just have a chat! For example, ask the candidate their opinions on the usefulness of VA scanners. The length of the response is as important as its technical accuracy. A long response gives an indication of passion for the field.
  • Getting on the security bandwagon too late (such as when you’re already in production!) you are looking at two choices – engage an experienced security hand and ignore their advice, or do not ignore their advice and face downtime, and massive disruption. Most will choose the first option and run the project at massive business risk.

The Security Challenge

Infosec is important, just as checking to see if cars are approaching before crossing the road is important. And the complexity of infosec mandates architecture. Civil engineering projects use architecture. There’s a good reason for that – which doesn’t need elaborating on.

Collapsing buildingWhenever you are trying to build something complex with lots of moving parts, architecture is used to reduce the problem down to a manageable size, and help to build good practices in risk management. The end goal is protective monitoring of an infrastructure that is built with requirements for meeting both risk and compliance challenges.

Because of the complexity of the challenge, it’s good to split the challenge into manageable parts. This doesn’t require talking endlessly about frameworks such as SABSA. But the following six capabilities (people, process, technology) approach is sleek and low-footprint enough for fintechs:

  • Threat and Vulnerability Management (TVM)
  • Logging – not “telemetry” or Threat intelligence, or threat hunting. Just logging. Not even necessarily SIEM.
  • Cryptography and Key Management
  • Identity Management
  • Business Continuity Management
  • Trust (network segmentation, firewalls, proxies).

I will cover these 6 areas in the next two articles, in more detail.

The above mentioned capabilities have an engineering and architecture component and cover very briefly the roles of security engineers and architects. A SABSA based approach without the SABSA theory can work. So an architect takes into account risk (maybe with a threat modelling approach) and compliance goals in a High Level Design (HLD), and generates requirements for the Low Level Design (LLD), which will be compiled by a security engineer. The LLD gives a breakdown of security controls to meet the requirements of the HLD, and how to configure the controls.

Security Engineers and Devops Tools

What happens when a devops peep interviews a security peep? Well – they only have their frame of reference to go by. They will of course ask questions about devops tools. How useful is this approach? Not very. Is this is good test of a security engineer? Based on the security requirements for fintechs, the answer is clear.

Security engineers can use devops tools, and they do, and it doesn’t take a 2 week training course to learn Ansible. There is no great mystery in Kubernetes. If you hire a security engineer with the right background (see the previous post in this series) they will adapt easily. The word on the street is that Terraform config isn’t the greatest mystery in the world and as long as you know Linux, and can understand what the purpose of the tool is (how it fits in, what is the expected result), the time taken to get productive is one day or less.

The point is: if i’m a security engineer and i need to, for example, setup a cloud SIEM collector: some fintechs will use one Infrastructure As Code (IaC) tool, others use another one – one will use Chef, another Ansible, and there are other permutations. Is a lack of familiarity with the tool a barrier to progress? No. So why would you test a security engineer’s suitability for a fintech role by asking questions about e.g. stanzas in Ansible config? You need to ask them questions about the six capabilities I mentioned above – i.e. security questions for a security professional.

Security Engineers and Clouds

Again – what was the transition period from on-premise to cloud? Lets take an example – I know how networking works on-premise. How does it work in cloud? There is this thing called a firewall on-premise. In Azure it’s called a Network Security Group. In AWS its called a …drum roll…firewall. In Google Cloud its called a …firewall. From the web-based portal UI for admin, these appear to filter by source and destination addresses and services, just like an actual non-virtual firewall. They can also filter by service account (GCP), or VM tag.

There is another thing called VPN. And another thing called a Virtual Router. On the world of on-premise, a VPN is a …VPN. A virtual router is a…router. There might be a connection here!

Cloud Service Providers (CSP) in general don’t re-write IT from the ground up. They still use TCP/IP. They host virtual machines (VM) instead of real machines, but as VMs have operating systems which security engineers (with the right background) are familiar with, where is the complication here?

The areas that are quite new compared to anything on-premise are areas where the CSP has provided some technology for a security capability such as SIEM, secrets management, or Identity Management. But these are usually sub-standard for the purpose they were designed for – this is deliberate – the CSPs want to work with Commercial Off The Shelf (COTS) vendors such as Splunk and Qualys, who will provide a IaaS or SaaS solution.

There is also the subject of different clouds. I see some organisations being fussy about this, e.g. a security engineer who worked a lot with Azure but not AWS, is not suitable for a fintech that uses AWS. Apparently. Well, given that the transition from on-premise to cloud was relatively painless, how painful is it to transition from Azure to AWS or …? I was on a project last summer where the fintech used Google Cloud Platform. It was my first date with GCP but I had worked with AWS and Azure before. Was it a problem? No. Do i have an IQ of 160? Hell no!

The Wrap-up

Problems we see in fintech infosec hiring represent what is most likely a lack of understanding of how they can best manage risk with a budget that is considerably less than a large MNC for example. But in security we haven’t been particularly helpful for fintechs – the problem is on us.

The security challenge for fintechs is not just about SAST/DAST of their code. The challenge is wider and be represented as six security capabilities that need to be designed with an architecture and engineering view. This sounds expensive, but its a one-off design process that can be covered in a few weeks. The on-going security challenge, whereby capabilities are pushed through into the final security operations stage, can be realised with one or two security engineers.

The lack of understanding of requirements in security leads to some poor hiring practices, the most common of which is to interview a security engineer with a devops guru. The fintech will be rejecting lots of good security engineers with this approach.

In so many ways, the growth of small to medium development houses has exposed the weaknesses in the infosec sector more than they were ever exposed with large organisations. The lack of the sector’s ability to help fintechs exposes a fundamental lack of skilled personnel, more particularly at the strategic/advisory level than others.

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Fintechs and Security – Prologue

A Match Made In Heaven?

Well, no. Far from it actually. But again, as i’ve been repeating for 20 years now, its not on the fintechs. It’s on us in infosec, and infosec has to take responsibility for these problems in order to change. If i’m a CTO of a fintech, I would be confused at the array of opinions and advice which vary radically from one expert to another

But there shouldn’t be such confusion with fintech challenges. Confusion only reigns where there’s FUD. FUD manifests itself in the form of over-lengthy coverage and excessive focus on “controls” (the archetypal shopping list of controls to be applied regardless of risk – expensive), GRC, and “hacking/”[red,blue,purple,yellow,magenta/teal/slate grey] team”/”appsec.

Really what’s needed is something like this (in order):

  • Threat modelling lite – a one off, reviewed periodically.
  • Architecture lite – a one off, review periodically.
  • Engineering lite – a one off, review periodically.
  • Secops lite – the result of the previous 3 – an on-going protective monitoring capability, the first level of monitoring and response for which can be outsourced to a Managed Service Provider.

I will cover these areas in more details in later episodes but what’s needed is, for example, a security design that only provides the answer to “What is the problem? How are we going to solve it?” – so a SIEM capability design for example – not more than 20 pages. No theory. Not even any justifications. And one that can be consumed by non-security folk (i.e. it’s written in the language of business and IT).

Fintechs and SMBs – How Is The Infosec Challenge Unique?

With a lower budget, there is less room for error. Poor security advice can co-exist with business almost seamlessly in the case of larger organisations. Not so with fintechs and Small and Medium Businesses (SMBs). There has been cases of SMBs going under as a result of a security incident, whereas larger businesses don’t even see a hit on their share price.

Look For A Generalist – They Do Exist!

The term “generalist” is seen as a four-letter word in some infosec circles. But it is possible for one or two generalists to cover the needs of a fintech at green-field, and then going forward into operations, its not unrealistic to work with one in-house security engineer of the right background, the key ingredients of which are:

  • Spent at least 5 years in IT, in a complex production environment, and outgrew the role.
  • Has flexibility – the old example still applies today – a Unix fan has tinkered with Windows. So i.e. a technology lover. One who has shown interest in networking even though they’re not a network engineer by trade. Or one who sought to improve efficiency by automating a task with shell scripting.
  • Has an attack mindset – without this, how can they evaluate risk or confidently justify a safeguard?

I have seen some crazy specialisations in larger organisations e.g. “Websense Security Engineer”! If fintechs approached security staffing in the same way as larger organisations, they would have more security staff than developers which is of course ridiculous.

So What’s Next?

In “On Hiring For DevSecOps” I covered some common pitfalls in hiring and explained the role of a security engineer and architect.

There are “fallback” or “retreat” positions in larger organisations and fintechs alike, wherein executive decisions are made to reduce the effort down to a less-than-advisable position:

  • Larger organisations: compliance driven strategy as opposed to risk based strategy. Because of a lack of trustworthy security input, execs end up saying “OK i give up, what’s the bottom line of what’s absolutely needed?”
  • Fintechs: Application security. The connection is made with application development and application security – which is quite valid but the challenge is wider. Again, the only blame i would attribute here is with infosec. Having said that, i noticed this year that “threat modelling” has started to creep into job descriptions for Security Engineers.

So for later episodes – of course the areas to cover in security are wider than appsec, but again there is no great complication or drama or arm-waiving:

  • Part One – Hiring and Interviews – I expand on “On Hiring For DevSecOps“. I noticed some disturbing trends in 2019 and i cover these in some more detail.
  • Part Two – Security Architecture and Engineering I – Threat and Vulnerability Management (TVM)
  • Part Three – Security Architecture and Engineering II – Logging (not necessarily SIEM). No Threat Hunting, Telemetry, or Threat “Intelligence”. No. Just logging. This is as sexy as it needs to be. Any more sexy than this should be illegal.
  • Part Four – Security Architecture and Engineering III – Identity Management (IDAM) and Cryptography and Key Management (CKM).
  • Part Five – Security Architecture and Engineering IV – Trust (network trust boundary controls – e.g. firewalls and forward proxies), and Business Resilience Management (BRM).

I will try and get the first episode on hiring and interviewing out before 2020 hits us but i can’t make any promises!

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