A detailed comparison of security audit companies

Security Audits · March 2026

I’ve hired, fired, competed against, and been ghosted by most of the firms on this list. Here’s what nobody’s sales deck will tell you.

Before I get into my wildly subjective opinions, let’s start with the facts. This table covers the criteria that actually matter when you’re writing a check for a security audit. Everything rated on a scale of ★★★★★. These ratings are mine — argue with me on LinkedIn.

Ratings based on my personal experience, conversations with clients, and public reputation. Your mileage may vary. Void where prohibited. Do not taunt Happy Fun Ball.

Here’s my pitch, stripped of all marketing: we do manual penetration testing, vulnerability assessments, and compliance audits, and we do them with people who actually know how to hack things. No armies of junior consultants running automated scanners and copy-pasting results into a 200-page PDF that nobody reads. Our reports are written by the same people who did the testing, which means they actually make sense.

We specialize in SOC 2, NIST 800-53, NIST 800-171, and ISO 27001. When a fintech needs to pass their SOC 2 audit and actually improve their security posture rather than just check boxes, they call us. When a defense contractor needs NIST 800-171 and can’t afford to fail the DIBCAC assessment, they call us. When a startup’s enterprise prospect sends over a 47-page security questionnaire with a one-week deadline, they call us in a panic at 11 PM, and we answer.

Our turnaround is fast — not because we cut corners, but because we don’t have seven layers of project management between the client and the person doing the work. You talk to your tester. Directly. On Slack. Like a human being.

Are we cheaper than Deloitte? Yes — roughly the same way that a Michelin-star restaurant is cheaper than renting the entire Four Seasons for dinner. Are we more expensive than some offshore pentest shops? Also yes. You get what you pay for, and what you pay for with us is people who will find the vulnerability that would have made the news.

“We don’t sell fear. We sell clarity. Here’s what’s broken, here’s how to fix it, here’s what to prioritize. That’s the whole business model.”

I have enormous respect for Mandiant, and I’m not just saying that because their threat intel reports have saved my skin more than once. These are the people who named APT1. They’ve responded to more nation-state breaches than most security firms have had clients. Their red team is genuinely terrifying in the best possible way.

The catch? They’re expensive. Not “oh that’s a bit steep” expensive. More like “let me sit down and have a glass of water” expensive. A full red team engagement can run into six figures faster than you can say “budget approval.” And since Google acquired them, the sales process has gotten... Googley. Expect forms, NDAs, and a procurement process that could double as cardio.

But if someone is actively in your network and you need the best incident response team on the planet? Mandiant. No contest. Just start a GoFundMe first.

Cobalt pioneered the Pentest-as-a-Service (PTaaS) model before “as-a-service” was slapped onto everything including laundry. Their platform connects you with a vetted pool of pentesters, lets you scope the engagement through a dashboard, and delivers findings in real-time rather than waiting three weeks for a PDF.

I like Cobalt for what they are: fast, repeatable, and developer-friendly. If you’re shipping code every sprint and need continuous testing that integrates with Jira, they’re solid. Their DAST, SAST, and network security testing covers the bases well.

Where I’d pump the brakes: the crowdsourced model means quality can vary. You might get a wizard who finds your critical auth bypass in two hours, or you might get someone who spends three days finding that your SSL certificate is using TLS 1.0 (congratulations, so could a free online scanner). The platform mitigates this with ratings and vetting, but it’s not quite the same as having a dedicated team that knows your environment.

Kroll has been around since before “cybersecurity” was even a word — they started as a corporate investigations firm in the 1970s. They’ve since built a respectable cyber practice that combines penetration testing with threat modeling, ransomware preparedness assessments, and incident response.

I once attended a Kroll-led tabletop exercise that was genuinely one of the best I’ve seen. Their scenario design felt like it was written by someone who had actually lived through a real incident, because it was. Their IR retainers are popular with mid-to-large enterprises who want someone on speed dial when things go sideways.

The downside? They’re a big firm, and they feel like one. Proposals take time. Kickoff meetings have agendas. There are account managers, engagement managers, and possibly a manager of managers. If you need a quick pentest of your web app before a product launch next month, Kroll might still be scheduling the scoping call.

Ah, Deloitte. The security audit firm you hire when you need to tell your board you hired Deloitte. Look, I’m going to be fair here: Deloitte has some genuinely brilliant cybersecurity people. The problem is that they also have approximately 415,000 other employees, and the odds of getting the brilliant ones are roughly the same as finding a parking spot in Manhattan on a Friday.

Their compliance expertise is genuinely top-tier — if you’re navigating a complex regulatory landscape across multiple jurisdictions, they can field an army of consultants who speak fluent SOX, PCI-DSS, HIPAA, and whatever acronym gets invented next Tuesday. Their reports look beautiful. Professionally typeset. Color-coordinated. Charts that would make Edward Tufte weep.

The actual penetration testing? In my experience, it ranges from excellent to “did an intern do this?” — and you won’t know which one you’re getting until you’re three weeks into a six-figure engagement. The senior partner who sold you the project will not be the person doing the work. That person will be several org-chart levels below, possibly on their second week.

Also, the timeline. My God, the timeline. I once watched a Deloitte scoping process take longer than the actual audit. By the time they delivered the final report, the application had been through two major version upgrades and a complete rewrite of the authentication system.

Astra has built a solid PTaaS platform that combines automated scanning with manual testing. They’re popular with SaaS companies — particularly startups who need a pentest report for their SOC 2 audit but don’t want to spend their Series A money on Mandiant.

Their marketing claims “zero false positives,” which — look, I respect the ambition, but that’s like a weather app claiming 100% accuracy. In my experience, their automated scanning is decent and their manual verification layer does catch most of the noise. The platform UI is clean, the reporting integrates with developer workflows, and the pricing won’t make your CFO cry.

Where Astra falls short is on complex environments. If you’ve got a microservices architecture with 47 APIs, custom authentication flows, and a legacy system held together with duct tape and stored procedures from 2008, you need human expertise that goes deeper than what their model currently delivers.

Nobody publishes their real prices, so here are the ranges I’ve seen in the wild for a standard web application penetration test. If a vendor quotes you outside these ranges, either you’re getting a deal or you’re getting fleeced.

Ranges are approximate and based on a typical mid-size engagement. Your actual quote will depend on scope, complexity, number of assets, compliance framework, timeline, and whether the salesperson had a good breakfast.

Some companies on the original list are great at what they do — but what they do isn’t really security auditing. Let me explain before their marketing teams send me angry emails.

Because “security audit” means wildly different things depending on who you ask. This table shows what each firm actually delivers versus what their sales page implies.

After a decade in this industry, here are the questions I wish every buyer would ask before signing. These are the questions that make bad vendors uncomfortable and good vendors excited.

I’ll make this stupidly simple. Here’s my recommendation based on what you actually need:

“The best security audit company isn’t the one with the fanciest website or the most conference booths. It’s the one whose testers find the vulnerability that would have cost you millions — and then help you fix it before anyone else finds it.”

Here’s what I’ve learned after years of watching companies pick security audit firms: the biggest risk isn’t hiring the wrong firm. It’s hiring any firm and then ignoring the results.

I’ve seen companies pay $200K for a Mandiant engagement, receive a masterful report detailing critical vulnerabilities, and then file it in a SharePoint folder titled “FY2024 Compliance Docs” where it quietly gathers digital dust for eighteen months. I’ve watched startups get a pentest report showing an authentication bypass that would let any anonymous user access admin functions, and then prioritize a CSS redesign of the login page instead.

A security audit is not a checkbox. It’s not a PDF you wave at your auditors during SOC 2. It’s a conversation between someone who just tried to break your systems and you, the person responsible for keeping them safe. If you’re not going to act on the findings, save your money and buy everyone on the team noise-canceling headphones instead. At least they’ll enjoy those.

But if you’re ready to take it seriously — to read the report, prioritize the findings, fix the critical issues, and build security into your culture rather than bolting it on once a year — then any of the genuine audit firms on this list will serve you well. Even Deloitte. (I can’t believe I just typed that.)

Choose wisely. Fix promptly. And for the love of everything sacred, don’t let anyone charge you $85K for a Nessus scan.

Ready for a Security Audit That Actually Finds Things?

Atlant Security delivers manual penetration testing, vulnerability assessments, and compliance audits with reports your developers will actually read. No scanner dumps. No filler. No surprises on the invoice.

No 47-slide sales deck. Just a real conversation about your security needs.

Published: March 2026 · Author: Alexander Sverdlov, Founder of Atlant Security

This article reflects the author’s personal opinions based on industry experience. The author is the founder of Atlant Security, which is featured in this comparison. Pricing ranges are approximate and based on publicly available information and industry conversations. Your actual experience with any firm may vary. All trademarks belong to their respective owners. No security auditors were harmed in the writing of this article, though a few egos may have been bruised.