Cross-site scripting lets an attacker run code in your users' browsers — stealing sessions and data, and turning your own site against your customers. This is dedicated XSS testing for Cyprus applications: context-aware payloads for reflected, stored and DOM-based XSS, delivered as a focused part of a full web application penetration test.
The hard part of XSS is context: the same input may be safe in one place and exploitable in another. We test each injection point in its real output context — HTML, attribute, JavaScript, URL — and check whether your CSP actually contains an attack or just looks like it does.
DOM-based XSS is invisible to server-side scanners because the flaw lives in client JavaScript — exactly where modern Cyprus web products put more and more logic. Finding it takes reading the front-end, not just fuzzing the back-end.
What we test
Reflected XSS across every input and context
Stored/persistent XSS in saved content
DOM-based XSS in client-side JavaScript
Mutation XSS (mXSS) and parser quirks
Filter, encoder and WAF bypass
Content-Security-Policy (CSP) evaluation
Common vulnerabilities we uncover
Session hijacking via stored XSS
Credential and keystroke theft
DOM-based XSS in single-page apps
Account takeover through script injection
CSP misconfiguration and bypass
Phishing and UI redressing via injection
How we run your engagement
Kick-off & scoping. A short call to agree goals, in-scope assets and rules of engagement, so your cross-site scripting (xss) testing is safe, authorised and aimed at your real business risk.
Mapping & discovery. Before touching anything we map the full attack surface in scope, so nothing exploitable slips through.
Hands-on testing. Cyprus-based specialists exploit and chain weaknesses manually — the flaws scanners walk straight past — to show genuine impact.
Reporting. Each issue is verified, CVSS-rated and documented with a step-by-step reproduction and a practical fix your team can apply.
Free retest. Once you have remediated, we re-test at no extra cost to confirm the attack path is truly closed.
Tools & techniques
We work by hand, crafting payloads for the specific sink and encoding in play and bypassing filters where they are weak, then proving impact with a benign but unmistakable demonstration. DOM XSS is hunted by reading the JavaScript, not guessing at it.
For client-heavy apps this pairs with our SPA penetration testing, and it sits within full web application penetration testing for end-to-end coverage.
When you need this engagement
Your app reflects or stores user-controlled content
You run a JavaScript-heavy or single-page front-end
You rely on a WAF or filter you want validated
You handle sessions or sensitive actions in-browser
You need confirmed, exploitable proof of XSS
What you receive
Confirmed XSS findings with working payloads
Context and sink documented per finding
Output-encoding and CSP remediation guidance
Reproduction steps for developers
Attestation letter where required
Complimentary retest after fixes
Your deliverables
When your cross-site scripting (xss) testing wraps up, you receive a clear, audit-ready report plus a walkthrough call with your team. Inside you will find:
A concise executive summary that management and the board can act on
Every technical finding with a reproducible, copy-paste proof of concept
CVSS v3.1 ratings and plain-language business impact for each issue
Practical, prioritised remediation your developers can implement straight away
A free retest and updated finding status once fixes are in place
A signed attestation letter for clients, auditors, GDPR, NIS2 and ISO 27001
Standards & frameworks
OWASP Top 10 A03: InjectionOWASP WSTGCWE-79Content Security Policy Level 3
What you gain
By the end of your cross-site scripting (xss) testing, you will know exactly which weaknesses a real attacker could exploit, what it would cost your business, and the precise order in which to fix them — backed by evidence, not a scanner’s guesswork. Cyprus firms use our findings to close critical gaps, satisfy client and regulator security questionnaires, and demonstrate due diligence for GDPR and NIS2. With a free retest included, you also get documented proof the issues are resolved.
Working with us
Every cross-site scripting (xss) testing begins with a short, no-obligation scoping call to understand your goals, environment and constraints, followed by a fixed-price proposal. Most work is delivered remotely, and because we are based in Cyprus we work in your timezone with on-site visits across Limassol, Nicosia and island-wide where it helps. We keep you updated throughout and flag any critical finding immediately rather than waiting for the report. Everything is covered by a signed NDA and safe, non-disruptive testing that protects your production systems. You receive your report, a walkthrough and a complimentary retest once fixes land. Engagements are typically booked one to three weeks ahead, and urgent testing can often be arranged — just email hi@cypruspentest.com.
Why Cyprus businesses choose CyprusPentest
Your cross-site scripting (xss) testing is run by senior offensive-security specialists who test the way genuine attackers do — manually, creatively and focused on proving real impact. What sets us apart:
Based in Cyprus — local, in your timezone, with on-site coverage across Limassol and Nicosia.
Manual, exploit-led testing that chains vulnerabilities the way an attacker would, well beyond automated scanners.
Reproducible proof for every finding, with copy-paste steps your team can independently verify.
Compliance-ready reporting that supports GDPR, NIS2, ISO 27001 and CySEC expectations.
A free retest so you have documented evidence your fixes actually hold.
Fixed-price and responsive, with a named point of contact from scoping through to retest.
Explore related services
Cross-Site Scripting (XSS) Testing pairs well with our other Cyprus penetration testing services for fuller coverage. You may also want:
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How much does Cross-Site Scripting (XSS) Testing cost?
Every cross-site scripting (xss) testing in Cyprus is scoped and priced individually, so you pay only for the coverage you need — with no hidden extras. After a short, no-obligation scoping call we send a fixed-price quote, usually within one business day, with clear deliverables, a firm timeline and a complimentary retest included. The price depends on the size and complexity of your environment, so you always know the cost up front before any work begins.
