Pen testing · Professional services
Penetration Testing for Law Firms
A penetration test shows your firm how an attacker would actually get to matter files and trust money, before one does. Firms typically book testing when a major client's questionnaire asks for independent evidence, when insurance renewal probes the security section, or after moving the DMS to the cloud. Because most practices run on SaaS, the test focuses on what you control: the Microsoft 365 tenant, remote access, portals and the office network.
Reviewed by the Privacy Horizon team · Last reviewed
What you're protecting
Where testing matters in a SaaS-based practice
A firm with no server room still has an attack surface. Testing concentrates on the layers you configure yourself, because that is where law-firm breaches actually start.
Email and identity in the tenant
Mailboxes hold privileged threads with clients and opposing counsel, and the accounts behind them are the keys to everything else. Weak conditional access or forgotten legacy sign-in protocols undo every other control.
Remote access paths
VPNs, remote desktop and whatever the MSP left listening on the internet deserve hostile attention. Exposed remote entry points are a proven way into small firms.
Client portals and sharing links
Portals for exchanging discovery, closing documents and drafts, and the share links your DMS generates, expose matter content to the web by design. They need testing as applications, not just as features.
The office network itself
Scanners, printers holding copies of ID documents, guest Wi-Fi and the accounting workstation that touches the trust ledger form the on-premises slice of risk most firms forget.
Regulatory map
Why regulators and clients expect firms to test
No statute orders a pen test by name. The expectation arrives through conduct rules about competence, records security and the contractual demands of the clients who pay you.
Competence you can evidence
Alberta's Code commentary on technological competence, echoed across the provinces, expects lawyers to understand the risks in the tools they use. A test converts that expectation from opinion into findings.
Reasonable means in Quebec
The Barreau's Guide des TI requires lawyers to take reasonable means so confidential information in the cloud cannot be read or intercepted by unauthorized third parties. Testing is how you verify the means are working.
What the LSO expects after an attack
The Law Society of Ontario's cybersecurity checklist walks firms through isolation, insurer notification and reporting through LSO Connects. Testing beforehand is how you avoid needing that document.
Insurers and OCGs ask directly
Cyber-insurance applications above the LAWPRO cybercrime sublimit, and the outside-counsel guidelines of institutional clients, frequently request recent independent testing as a condition of coverage or work.
What goes wrong
What a pen test surfaces before an attacker does
The findings that matter to a firm are the ones that lead to privileged files or money in trust. These are the patterns testing reliably uncovers.
Brute-forceable entry points
The 2023 intrusion at a twelve-lawyer Ottawa firm began with brute force against an exposed service and went undetected for weeks. Testing finds those doors and measures whether anyone notices the knocking.
Mailbox takeover conditions
Missing MFA enforcement, weak reset flows and stale accounts of departed clerks create the conditions for the compromised-email fraud that law society and insurer guidance keeps warning about.
Leaky document sharing
Links that never expire, portals that reveal one client's uploads to another, and downloads that skip authentication all turn routine file exchange into quiet disclosure.
Credentials already in circulation
Passwords reused between personal accounts and the practice-management login are a standing hazard for small firms. Controlled password attacks show whether yours would hold.
Our pen testing for law firms
What our penetration testing covers for a firm
Scope is agreed in writing before anything is touched, matched to what your clients' questionnaires and your insurer actually want evidenced.
External exposure testing
Everything your firm presents to the internet, from mail routing and remote access to forgotten subdomains, probed the way an opportunistic attacker would.
Tenant configuration review
Vulnerability exploration across your Microsoft 365 or Google Workspace setup: authentication policies, sharing defaults, mail rules and administrative sprawl.
Portal and web application testing
Hands-on testing of client portals, intake forms and document-exchange tools, covering authentication, authorization between matters, and link handling.
Detection and response observation
We note what your MSP or monitoring actually flags during the exercise, which tells you whether a real intrusion would be caught in hours or discovered in a month.
Findings partners can rank
A report separating what threatens privilege and trust funds from what is merely untidy, with directional fixes, plus a summary letter suitable for client and insurer evidence requests.
How the engagement runs
Running a test without disrupting practice
Law firms cannot tolerate downtime during trials and closings, so scheduling is part of scoping, not an afterthought.
Step 1
Scope and rules of engagement
We define targets, exclusions and blackout windows around closings, filing deadlines and trial dates, and confirm authorization for anything hosted by a third party.
Step 2
Controlled testing
Testing proceeds in agreed windows with a live contact channel, so anything sensitive discovered is escalated immediately rather than saved for the report.
Step 3
Debrief with your people
Findings are walked through with the managing partner and the MSP together, so remediation ownership is assigned in the room rather than argued about later.
Step 4
Evidence and follow-up
You receive the full report and the shareable summary, and once fixes land we verify the closures so your questionnaire answers stay truthful.
What it costs
What drives penetration testing cost for firms
Price scales with the surface under test: how much you expose externally, whether the tenant review and office network are included, how many portals and web applications you run, and whether client evidence requirements force a specific methodology or a retest. A focused external test for a boutique is materially smaller than a full exercise for a multi-office firm with a real-estate practice.
Send over the security section of the questionnaire or renewal that prompted the call, and we will quote a scope that answers it exactly.
Law Firms: Pen testing questions, answered
Need is driven by your clients, your insurer and your risk tolerance rather than by a statute. When everything is SaaS, the test covers what remains yours: identity and authentication, tenant configuration, remote access, integrations between practice systems, the office network and the human-facing surfaces like portals. That layer is where firm breaches begin, because vendors secure their platforms but not your settings, passwords or sharing habits.
Usually it satisfies the testing line, provided the scope matches what the questionnaire asks about. If the client wants evidence of application testing and you only tested the perimeter, the answer will not hold up. That is why we ask to see the actual questionnaire during scoping and shape the exercise around it. You receive a summary letter written for exactly this purpose, so you can respond without circulating the full technical report outside the firm.
Yes, and for most firms this is the most valuable part of the exercise. We test whether one client could reach another matter's documents, whether sharing links expire and resist guessing, whether authentication can be bypassed or brute-forced, and what an uploaded malicious file would do. Where the portal is a vendor product, we test your configuration and obtain the vendor's permission where their terms require it.
This concern is legitimate and is exactly why blackout windows exist. Testing is scheduled around your court calendar and closing dates, destructive techniques are excluded by the rules of engagement, and a live escalation channel means we pause instantly if anything looks unstable. In practice, disruption is rare; the real operational cost is a few hours from your MSP and administrator during scoping and debrief.
Not their platforms; those belong to the vendors, and attacking them without authorization is off the table. What we can test is everything the vendor leaves in your hands: your authentication and MFA enforcement, user and permission sprawl, sharing settings, API keys and integrations, and how the product is wired into your tenant. Vendor-side assurance comes from their own certifications and reports, which our vendor security review service evaluates.
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