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GoldAgent

Authorised assessment

VoIP Penetration Testing

An authorised penetration test of your VoIP and SIP estate that goes beyond a scanner: a specialist confirms which weaknesses are genuinely exploitable and shows the business impact, safely and under written scope.

Request this assessmentHow we work

This is active, authorised testing. We confirm scope and written authorisation before any active work begins, including a hosted provider's consent where required.

The problem

A scan lists issues; a penetration test proves what an attacker could do

Automated vulnerability scanners are useful, but they report possibilities, not proof. They flag an open SIP port or an old version and leave you to guess whether it matters. On telephony that guess is expensive, because the outcome that matters, fraudulent call spend, depends on how registration, authentication and dialling behave together, not on a single version string.

What we commonly find

  • Scanners raise findings a scanner cannot confirm or exploit
  • Version banners do not tell you whether authentication actually holds
  • Toll-fraud risk depends on dial-plan and routing behaviour, not open ports alone
  • False positives waste engineering time; missed exploit paths cost money
  • Generalist network tests rarely understand SIP registration or media

The approach

Authorised, manually validated telephony penetration testing

GoldAgent runs the active checks a specialist telephony penetration test requires, then a person validates each finding by hand and, where authorised, demonstrates the impact in a controlled way. You get proof, not a list: what is exploitable, how, and what it would cost if left open.

  • Active testing of SIP registration, authentication and signalling
  • Dial-plan and routing tested for the paths that enable toll fraud
  • Every finding manually confirmed and de-duplicated before reporting
  • Impact demonstrated safely, under written authorisation and agreed limits
  • Evidence, severity and prioritised remediation you can act on, plus a retest

Methodology

How the engagement runs

  1. 1

    Define scope

    Agree the exact VoIP and SIP systems, addresses and services in scope, and what is explicitly out of scope.

  2. 2

    Confirm authorisation

    You confirm ownership or right-to-test in writing before any active work begins. Where a hosted provider's consent is required, it is confirmed first.

  3. 3

    Discover the estate

    Map the SIP endpoints, trunks, media paths and administrative interfaces reachable within the agreed scope.

  4. 4

    Test actively

    Exercise registration, authentication, signalling, media and dialling controls using lockout-aware techniques and an agreed emergency-stop contact.

  5. 5

    Validate and demonstrate

    Confirm each weakness is real and, where authorised, demonstrate its impact in a controlled, non-billable way.

  6. 6

    Prioritise

    Rank findings by severity, exploitability and business impact.

  7. 7

    Report

    Deliver a management summary plus technical detail, evidence and remediation guidance.

  8. 8

    Retest

    Re-check remediated findings and update their status.

What you receive

  • Executive summary written for decision-makers
  • Manually validated technical findings with severity ratings
  • Evidence for each finding and the affected SIP or VoIP component
  • Controlled proof of impact where authorisation allowed it
  • Prioritised, actionable remediation guidance
  • Retest status once fixes are applied

Who it suits

  • Organisations that want proof of exploitability, not just a scan report
  • Businesses preparing for Cyber Essentials, PCI DSS or an insurance renewal
  • IT and security teams migrating telephony to IP ahead of the PSTN switch-off
  • MSPs and resellers who need a specialist telephony test under their brand

Risks it addresses

  • Toll fraud

    Weak SIP authentication and permissive dial plans let attackers place expensive calls the business is usually liable for.

  • Call interception

    Unencrypted signalling or media and weak segmentation can expose call content.

  • Account abuse

    Exposed registration and management interfaces allow extensions to be hijacked and reconfigured.

FAQ

VoIP Penetration Testing: questions

How is this different from a VoIP security assessment?

The VoIP Security Assessment is a broad, outside-in review of your telephony attack surface. VoIP Penetration Testing is the active, manually validated engagement that confirms which of those weaknesses are genuinely exploitable and, where authorised, demonstrates the impact. Many clients start with an assessment and commission penetration testing where proof is needed.

Is this just an automated scan?

No. Automated tooling is used for coverage, but every finding is validated by a person and exploit paths are confirmed rather than assumed. You receive proof and evidence, not a raw scanner list.

Will testing disrupt our live phones?

Testing is planned around your environment with lockout-aware techniques and an agreed emergency-stop contact. Higher-impact tests run only with your explicit agreement.

Do you test hosted or cloud VoIP?

Yes, where the party with authority over the system authorises it. Where a hosted provider's consent is required, that is confirmed before any active work begins.

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Request a VoIP Penetration Testing

We confirm scope and authorisation first, then show you exactly what is exposed and what to fix.

Request an Assessment

Testing is only performed against systems you own or are explicitly authorised to test.