Start protecting my application
Continuous offensive security

Know what breaks before attackers do.

Zentinel continuously discovers, attacks and verifies your application's attack surface, so your team can ship faster without guessing what's actually exploitable.

Start protecting my applicationSee how Zentinel works

Assessments delivered in 48 hours*

DiscoverSweeping the whole attack surface
startups tested
28
security findings across them
200+
assessment delivery commitment*
48h
false positives shipped through our audit process
0
serious findings verified before delivery
100%

*The 48 hours start once scope, written authorization, target details and test access are confirmed. If access is delayed or the scope grows significantly, the clock pauses until it's resolved.

Fix with your agent

Works with the coding tool you already use.

Connect Zentinel to any AI coding agent that supports MCP, in two minutes. Findings go straight from our report to a fix in your codebase, and a security engineer still verifies every one.

  1. Your agent reads each verified finding with its fix
  2. It patches your code, runs your tests and commits
  3. It asks for a retest. We confirm the fix before it closes
Connect your agentSee pricing
  • Claude Code
  • Codex
  • Cursor
  • VS Code
  • JetBrains
  • Windsurf
  • Antigravity
  • Kiro
  • OpenCode
  • + many moreGitHub Copilot, Cline, Zed, Warp, Amp, Roo Code, Continue, Goose and any tool that supports MCP.

You choose what each key can do, and your agent can never close a finding.

A new release reality

Your application changes faster than your security does.

New code, new endpoints, new integrations, new login flows, new infrastructure. Every week.

Every change is a new attack path.

The Zentinel loop

Security doesn't end when the test ends.

Put your application into the Zentinel security loop.

  1. 01

    Discover

    Map the attack surface.

    Domains, APIs, endpoints, authentication, infrastructure and exposed services.

  2. 02

    Attack

    Test it like an attacker.

    Auth, authorization, APIs, business logic, injection, SSRF, tenant isolation, AI and chained paths.

  3. 03

    Prove

    Separate exploitable from theoretical.

    Every serious finding needs evidence.

  4. 04

    Prioritize

    Focus on what matters.

    The vulnerabilities and attack paths that create real risk, first.

  5. 05

    Fix

    A clear path forward.

    Actionable remediation, not a 200-page dump of scanner output.

  6. 06

    Retest

    Verify the fix.

    A closed ticket isn't proof the vulnerability is gone.

  7. 07

    Watch

    Keep testing as you change.

    Where Zentinel becomes continuous.

One-time assessments run Discover to Retest once. Continuous and Growth keep the loop running: Watch feeds the next Discover.
Why it's different

Security testing that doesn't stop at detection.

Don't trust the scanner. Prove the exploit.

  1. Most security tools“Something might be wrong.”
  2. Zentinel“Can I actually break it?”
  3. Zentinel“What does that give an attacker?”
  4. Zentinel“Did the fix actually work?”
01

Find what matters

Map the attack surface and identify the weaknesses that could actually matter to an attacker.

02

Prove what breaks

Reproduce serious vulnerabilities, establish impact and give your team evidence they can act on.

03

Stay ahead of change

Retest fixes and keep testing as your application, infrastructure and attack surface evolve.

The attack surface

One security engine.
Multiple attack surfaces.

Modern software doesn't live in one place. Zentinel tests the application, identities, APIs, cloud environment, AI systems, mobile clients and other surfaces attackers can use to reach it.

The application
01

Web & API security

Web applications, APIs, authentication, authorization, sessions, tenant isolation and data exposure.

02

Business logic & attack paths

Application-specific abuse, workflow manipulation, races, privilege boundaries and chained attacks.

03

Identity & access

Authentication flows, authorization boundaries, IDOR/BOLA, role escalation, token handling and tenant isolation.

Around the application
04

AI, agents & MCP

Prompt injection, indirect prompt injection, system-prompt exposure, tool abuse, agent authorization, unsafe tool arguments, MCP security and cross-user leakage.

More
05

Cloud security

AWS, Google Cloud and Azure reviews within scope: exposed services, storage, metadata, secrets, network exposure and cloud attack surface.

More
06

Mobile security

Android and iOS: client-side controls, authentication, API communication, secrets and mobile attack surfaces.

More
Everything you expose, as it changes
07

External attack surface

Domains, subdomains, ports, services, APIs, staging environments, admin interfaces, exposed files and internet-facing infrastructure.

08

Continuous verification

Release testing, retesting, security history and verification as the application changes.

More
AI security

Your AI application has a new attack surface.

LLMs, agents and MCP servers introduce new ways to manipulate your systems, abuse tools and reach data your users shouldn't be able to access.

  • Prompt injection
  • Indirect prompt injection
  • System prompt exposure
  • Tool abuse
  • Agent authorization
  • Unsafe tool arguments
  • MCP security
  • Cross-user leakage
  • Model and API key exposure
  • Agentic workflows
Cloud security

Your application doesn't end at the API.

Your cloud environment is part of your application's attack surface. Zentinel can review AWS, Google Cloud and Azure environments within scope to identify exposed services, storage, metadata, secrets and configuration risks.

  • AWS
  • Google Cloud
  • Azure
  • Exposed services
  • Storage
  • Metadata
  • Secrets
  • Network exposure
  • Configuration risk

Read-only access. No infrastructure changes.

Mobile security

Your mobile app is another front door.

Test the mobile client, the API behind it and the controls that connect them.

  • Android
  • iOS
  • Authentication
  • Authorization
  • API communication
  • Client-side controls
  • Local storage
  • Secrets
  • Configuration
  • Application attack surface
Under the hood

Built to hunt.

A layered offensive security engine combines automated discovery, adversarial testing and expert verification across the attack surfaces modern applications expose.

  1. L1ReconnaissanceAttack-surface discovery
  2. L2Application testingWeb, API, identity and access
  3. L3Adversarial testingBusiness logic and attack chains
  4. L4Specialized testingAI, MCP, mobile and cloud
  5. L5VerificationEvidence-backed security findings
Read the Zentinel methodology
From the findings ledger

What startup stacks keep getting wrong.

Across 200+ findings in 28 startups, the same classes keep coming back: broken sessions, unprotected APIs, exposed cloud origins and one customer reaching another's data.

They're rarely exotic. They're simply untested.

Every one of them was reproduced and verified before it reached the team that had to fix it. Read the attack stories

Findings ledger · recurring classes
  1. Authentication / session31
  2. API / MCP / GraphQL25
  3. Cloud / infra exposure (origins, buckets, DNS)24
  4. IDOR / BOLA / authorization19
  5. SSRF9
  6. Data exposure8
  7. Injection4
  8. Firebase / Supabase rules4
  9. Billing logic3
  10. Secrets2
Most frequent classes across 200+ findings in 28 startups. Customer details withheld.
Verification

Automation gives us scale. Verification gives you confidence.

Zentinel automates repetitive security testing so your application can be tested at scale. Serious findings are reproduced and validated before they reach your team.

  1. 01

    Machines find where to look.

    Automated discovery maps your reachable attack surface and identifies signals worth testing.

  2. 02

    Zentinel attacks.

    Automated and adversarial testing attempts to turn weaknesses into real security impact.

  3. 03

    Experts verify what matters.

    Serious findings are reproduced and validated before they reach your team.

Every serious finding is verified before delivery.If a finding doesn't meet Zentinel's verification standard, it doesn't become a customer-facing finding.
The annual pentest

Your annual pentest tested an application that no longer exists.

The problem isn't pentesters.
The problem is that your application keeps changing.

TraditionalZentinel
Once a yearRecurring
Point-in-timeContinuous loop
Find vulnerabilitiesFind and prove
A reportSecurity history
FixFix and retest
New release, new riskRelease-aware testing
Scanner outputVerified risk
A security projectA security system
Don't take our word for it

Attack stories, not testimonials.

What Zentinel found, what we proved, why it mattered, and the retest that confirmed the fix. Customer details are redacted.

All case studies
criticalCVSS 9.1

Signup form that reset anyone's password.

Re-registering an existing user's email allowed an attacker to take over the account.

  1. Discovered (complete)
  2. Proven (complete)
  3. Fixed (complete)
  4. Retested (complete)
Read the case study
criticalCVSS 10.0

Unauthenticated remote code execution.

A public-facing application accepted crafted input that resulted in server-side command execution.

  1. Discovered (complete)
  2. Proven (complete)
  3. Fixed (not yet published)
  4. Retested (not yet published)
Read the case study
criticalCVSS 10.0

Exposed BI tool with unauthenticated SQL injection.

An internal analytics instance was reachable from the public internet and exposed a path to sensitive company data.

  1. Discovered (complete)
  2. Proven (complete)
  3. Fixed (not yet published)
  4. Retested (not yet published)
Read the case study
Ways to start

Start where the risk is.

Use Zentinel for a focused security need, or put your application into the continuous loop.

Application assessment

Know what breaks before launch.

Release security

Test the feature you're about to ship.

Security retest

Prove the fix actually worked.

AI security

Test your LLMs, agents and MCP.

Cloud security

Review AWS, Google Cloud or Azure exposure.

Mobile security

Test Android and iOS attack surfaces.

Put my application into the Zentinel Loop
Who it's for

Built for teams that ship.

Startups

Security without building a dedicated offensive-security team.

SaaS companies

Protect APIs, authentication, tenants and integrations as the product evolves.

AI companies

Test LLMs, agents, tools and MCP before attackers do.

Product teams

Ship new features without waiting for an annual security cycle.

Engineering teams

Make offensive security part of the software lifecycle.

Pricing

Simple pricing. Serious security.

Start with one assessment. Put your application in the loop when you're shipping every week. What you paid is credited if you move to Continuous within 30 days.

You're not buying a scanner. You're buying:
  • Attack-surface intelligence
  • Offensive testing
  • Exploit verification
  • Prioritized remediation
  • Retesting
  • Security evidence
  • A repeatable security process

Launch

Know where you stand.

$299one-time

A serious security baseline before your next launch, customer deal or raise.

  • 1 application
  • Attack-surface discovery
  • Web, API, auth and business-logic testing
  • Verified, prioritized findings
  • Full report with remediation guidance
  • Retest within 30 days
  • Delivered in 48 hours

SOC 2-Ready

Built for the audit.

$2,500/ application

A penetration test built to hand to your SOC 2 auditor.

  • Penetration test with documented methodology
  • Technical findings with evidence
  • CVSS scoring
  • Remediation guidance
  • Retest
  • Audit-ready report and evidence package

Evidence for your audit, not an attestation: your SOC 2 auditor remains independent.

Free · $0

Exposure Check

Verify you own the domain with one DNS record, then get an outside-in snapshot: subdomains, certificates, headers, exposed technologies and likely exposures.

Run a free exposure check
  1. LaunchStart small.
  2. StartupProve value.
  3. ContinuousPut the app in the loop.
  4. GrowthEvery product, every release.
  5. EnterpriseExpand as you grow.
Specialist add-ons
  • Mobile $500 / platform
  • Cloud from $1,500
  • AI / MCP from $1,500
  • Source review from $1,500
  • Extra application $600 / month
  • Extra release test $250
Compare plans and add-ons
How it works

Security testing without the security project.

  1. 01ConnectTell Zentinel what you want tested.
  2. 02AuthorizeConfirm ownership and testing authorization.
  3. 03TestZentinel discovers and attacks the application.
  4. 04VerifySerious findings are reproduced and validated.
  5. 05FixYour team gets prioritized remediation guidance.
  6. 06RetestZentinel verifies the fix.
  7. 07Keep watchingRecurring plans continue the loop.
The team

Built by people who think like attackers.

Zentinel was built around a simple belief: modern software changes too quickly for security to be a once-a-year project.

So we built a system that continuously discovers the attack surface, tests it, verifies what breaks and keeps checking after the fix.

Alvin MugethiFounder, Zentinel
FAQ

Before you ask.

What Zentinel tests, how it works, and what happens after you buy.

Pricing and contract questions
Is this just an automated scanner?

No. Automation maps the attack surface and does the repetitive work at scale. Zentinel then tries to turn weaknesses into real impact, and every serious finding is reproduced and verified before it reaches you. If a finding doesn't meet the verification standard, it doesn't become a customer-facing finding.

How is Zentinel different from a traditional pentest?

A traditional pentest is a point-in-time snapshot. Zentinel runs a loop: discover, attack, prove, prioritize, fix, retest and, on continuous plans, keep watching as you ship. One-time assessments run the loop once and include a retest. Continuous plans keep it running with release tests and security history.

Do you need our source code?

No. Zentinel tests from the outside, the way an attacker would, using the target and test accounts you provide. Source-code review is available as an add-on where it makes testing of high-risk flows deeper.

Can you test production?

Yes, within the scope and rules of engagement you approve in writing. Testing is non-destructive by default: no load tests, floods or mass sign-ups. If you prefer, we test a staging copy instead.

What applications can you test?

Web applications and the APIs behind them, including authentication, authorization, business logic and tenant isolation. AI features, agents and MCP servers, mobile apps and cloud environments are covered through specialist reviews.

Can you test APIs?

Yes. REST and GraphQL APIs are core to every assessment: authentication, authorization (including IDOR/BOLA), data exposure, rate limits and business logic.

Can you test mobile applications?

Yes. A focused mobile review covers the Android or iOS client and the API behind it, and can be added at checkout per platform. Full mobile penetration tests are quoted.

Can you test AWS, Google Cloud and Azure?

Yes. Cloud security reviews of AWS, Google Cloud and Azure are run within scope using read-only access. Zentinel makes no infrastructure changes. This is a security review of your exposure, not a replacement for a cloud security platform.

Can you test AI applications and MCP?

Yes. Zentinel tests prompt injection (direct and indirect), system-prompt exposure, tool abuse, agent authorization, unsafe tool arguments, MCP security, cross-user leakage and model or API key exposure.

What happens when you find something?

Critical findings are reported to you the moment they are confirmed. Every finding comes with evidence, impact, a severity score and remediation guidance, prioritized so your team knows what to fix first.

Are findings verified?

Yes. Serious findings are reproduced and validated by a security expert before they reach your team, with the request, the response and the impact recorded as evidence.

How quickly do we receive the report?

Assessments are delivered within 48 hours. The clock starts once scope, written authorization, target details and test access are confirmed.

Will customers or auditors accept the report?

Each report covers scope, methodology, every finding with evidence and a CVSS score, remediation and the retest result: what security questionnaires and SOC 2 auditors ask for. The SOC 2-Ready assessment adds an audit-ready evidence package.

What happens after we fix something?

Zentinel retests it: the original attack is replayed and the result recorded. A retest is included on every plan: within 30 days on Launch, 60 days on Startup, and on an ongoing basis on Continuous and Growth.

Can Zentinel test every release?

Continuous and Growth include 2 release tests per application every month, alongside ongoing attack-surface monitoring. Additional release tests can be added from the portal.

Your application keeps changing.
Your security should keep testing.

Put your application into the Zentinel loop.

Start protecting my application

Authorized testing only. All testing occurs within agreed scope and rules of engagement.