Security - https://zalando.com BeaverCheck Audit

F

Security Headers

Action

2 of 10 headers properly configured

FIX

2 of 10 headers properly configured

HSTS header is missing

Strict-Transport-Security forces browsers to use HTTPS, preventing downgrade attacks. Add the header with a max-age of at least 1 year.

Expected: max-age=31536000; includeSubDomains

X-Content-Type-Options header is missing

This header prevents MIME-type sniffing, which can lead to XSS attacks. Set it to 'nosniff'.

Expected: nosniff

X-Frame-Options header is missing

This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.

Expected: DENY

Referrer-Policy header is missing

Controls how much referrer information is sent with requests. Set to 'strict-origin-when-cross-origin' or stricter.

Expected: strict-origin-when-cross-origin

Permissions-Policy header is missing

Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features.

Expected: geolocation=(), camera=(), microphone=()

Content-Security-Policy header is missing

CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.

Expected: default-src 'self'

Cross-Origin-Opener-Policy header is missing

COOP isolates your browsing context, preventing cross-origin side-channel attacks. Set to 'same-origin'.

Expected: same-origin

Cross-Origin-Embedder-Policy header is missing

COEP prevents loading cross-origin resources without explicit permission. Required for SharedArrayBuffer and high-resolution timers.

Expected: require-corp

X-Powered-By header is not present

Server header is present without version info

Got: CloudFront

Domain is not in the Chrome HSTS preload list (status: unknown)

Submit your domain to hstspreload.org to close the trust-on-first-use gap. Requires a preload-ready HSTS header (max-age=31536000+, includeSubDomains, preload).

Got: unknown

Strict-Transport-Security forces browsers to use HTTPS, preventing downgrade attacks. Add the header with a max-age of at least 1 year.

Expected: max-age=31536000; includeSubDomains

Why this matters

Without HSTS, a network attacker can downgrade the very first connection to HTTP and steal the user's session.

Learn more ▾

HSTS tells browsers 'never speak HTTP to this domain again.' Without it, a network attacker (public WiFi, malicious ISP, hostile DNS) intercepts the first HTTP attempt and serves a downgraded version of your site. One header, big surface reduction.

Source: RFC 6797 / OWASP

CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.

Expected: default-src 'self'

Why this matters

Without a CSP, a single XSS bug can exfiltrate everything your users type — including credentials.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies or rewrite the page is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever.

Source: OWASP / MDN

This header prevents MIME-type sniffing, which can lead to XSS attacks. Set it to 'nosniff'.

Expected: nosniff

Why this matters

MIME sniffing lets browsers run uploaded files as JavaScript, turning a file upload into an XSS.

Learn more ▾

Setting X-Content-Type-Options: nosniff tells browsers to trust your declared Content-Type instead of guessing. Without it, an attacker who uploads a polyglot file can sometimes get it executed as a script. One header, no downside.

Source: OWASP / MDN

This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.

Expected: DENY

Why this matters

Without frame protection, your site can be embedded in a hostile page and used for clickjacking.

Learn more ▾

Clickjacking overlays your site under a transparent malicious page so users click invisible buttons. Setting X-Frame-Options: DENY (or a modern frame-ancestors CSP directive) blocks the embedding entirely. There's almost never a legitimate reason to allow it.

Source: OWASP / MDN

Controls how much referrer information is sent with requests. Set to 'strict-origin-when-cross-origin' or stricter.

Expected: strict-origin-when-cross-origin

Why this matters

Default browser behavior leaks full URLs (including query params and tokens) to every third-party resource — set a strict policy.

Learn more ▾

Without a Referrer-Policy header, browsers send the full referring URL with images, scripts, and fonts loaded from third-party origins. URLs containing tokens, user IDs, or session params end up in third-party logs. Set `Referrer-Policy: strict-origin-when-cross-origin` (or stricter) to limit leakage.

Source: MDN / W3C

Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features.

Expected: geolocation=(), camera=(), microphone=()

Why this matters

Permissions-Policy locks down browser APIs you don't use — without it, every page can request camera/mic/geolocation if XSS lands.

Learn more ▾

By default every page can request the camera, microphone, geolocation, payment APIs, and dozens more. Permissions-Policy turns off the ones you don't need so a future bug can't quietly start using them. It's a defense-in-depth header — one line, big surface reduction.

Source: MDN / W3C

COOP isolates your browsing context, preventing cross-origin side-channel attacks. Set to 'same-origin'.

Expected: same-origin

Why this matters

COOP isolates your top-level browsing context from cross-origin windows — without it, popup-based side-channel attacks remain possible.

Learn more ▾

Cross-Origin-Opener-Policy: same-origin prevents cross-origin pages from sharing a browsing-context group with yours. This blocks cross-window references that enable Spectre-style timing attacks and tab-nabbing. Required if you want to enable SharedArrayBuffer.

Source: MDN / web.dev

COEP prevents loading cross-origin resources without explicit permission. Required for SharedArrayBuffer and high-resolution timers.

Expected: require-corp

Why this matters

COEP enforces that all embedded resources opt-in to cross-origin embedding — required for cross-origin isolation features.

Learn more ▾

Cross-Origin-Embedder-Policy: require-corp ensures every embedded resource (script, iframe, image) explicitly allows being loaded cross-origin. Combined with COOP, this enables the cross-origin-isolated context that unlocks SharedArrayBuffer, high-resolution timers, and other powerful APIs.

Source: MDN / web.dev

Submit your domain to hstspreload.org to close the trust-on-first-use gap. Requires a preload-ready HSTS header (max-age=31536000+, includeSubDomains, preload).

Why this matters

Not in the Chrome preload list — first-time visitors over plain HTTP can be downgraded by a network attacker before HSTS kicks in.

Learn more ▾

The HSTS header only protects users who have already visited the site (TOFU window). Adding your domain to the Chrome preload list closes that gap so HSTS is enforced from the very first connection. Requires a preload-ready header (max-age=31536000+, includeSubDomains, preload) then submission at hstspreload.org. Inclusion ships in the next Chrome release after acceptance.

Source: hstspreload.org

F

Content Security Policy

Action

No enforcing CSP policy found

FIX

No enforcing CSP policy found

No Content-Security-Policy header found

CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.

Expected: default-src 'self'

CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.

Expected: default-src 'self'

Why this matters

Without a CSP, a single XSS bug can exfiltrate everything users type — credentials, payment data, session tokens.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever. Start in Report-Only mode, fix violations, then graduate to enforcing.

Source: OWASP / MDN

D

Permissions-Policy

Action

No header set

FIX

No header set

No Permissions-Policy header

Consider adding a Permissions-Policy header to restrict browser feature access from embedded content.

No Permissions-Policy header set.

Without this header, embedded iframes can request access to sensitive device features.

Suggested header

Permissions-Policy: camera=(), microphone=(), geolocation=(), payment=(), usb=()

D

security.txt

Action

No /.well-known/security.txt published

FIX

security.txt

No security.txt found at /.well-known/security.txt

B

WAF / Bot Protection

No WAF detected via response headers

REVIEW

No WAF detected via response headers

No WAF detected

Response headers don't match any known WAF or bot-management product. Sites exposed to abuse (login, signup, payment) typically benefit from a WAF such as Cloudflare, Akamai, AWS WAF, or Imperva.

B

Email Security

DMARC: reject, DKIM

REVIEW

DMARC: reject, DKIM

DMARC policy is reject — strongest protection

DKIM configured (selectors: google)

MTA-STS not configured

MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.

TLS-RPT not configured

TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.

DMARC

Policy reject — strongest protection Record v=DMARC1; p=reject; fo=1; rua=mailto:dmarc_rua@zalando.com; ruf=mailto:dmarc_ruf@zalando.com; adkim=s; pct=100;

MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.

Why this matters

Without MTA-STS, inbound mail can be silently downgraded to plain SMTP by a network attacker.

Learn more ▾

MTA-STS (RFC 8461) tells sending mail servers to use TLS and to refuse delivery if TLS fails. Requires both a TXT record at _mta-sts.<domain> AND a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt. Without it, an active attacker on the network path can strip STARTTLS and read the email in plaintext.

Source: RFC 8461

TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.

Why this matters

Without TLS-RPT, you have no visibility into inbound TLS failures — MTA-STS misconfigurations stay hidden until users complain.

Learn more ▾

TLS-RPT (RFC 8460) is the feedback channel for MTA-STS: senders post aggregate reports of TLS-handshake failures to the URI in your _smtp._tls TXT record. Without it, an MTA-STS misconfiguration silently rejects mail and you find out only when someone notices missing email.

Source: RFC 8460

B

CORS Configuration

No CORS headers

REVIEW

No CORS headers

No CORS headers present — secure default

CORS Configuration ✓ Secure

No CORS headers detected.

Cross-origin requests are blocked by browser same-origin policy.

Origin reflection test

Some servers mirror the request Origin header, which can be exploited. Test manually:

curl -sI -H "Origin: https://evil.com" <url> | grep -i access-control

B

Transport Security

HTTP/3, HSTS, and TLS version analysis

REVIEW

HTTP/3, HSTS, and TLS version analysis

HTTP/3 (QUIC) not advertised

HTTP/3 eliminates head-of-line blocking. If your CDN supports it, consider enabling it.

Missing Strict-Transport-Security header

HSTS tells browsers to only use HTTPS, preventing SSL stripping attacks.

TLS 1.3 in use (fastest handshake, 1-RTT)

A+

TLS & Certificates

TLS 1.3, 8 checks passed

PASS

TLS 1.3, 8 checks passed

TLS 1.3 is used

Got: TLS 1.3

Strong cipher suite is used

Got: TLS_AES_128_GCM_SHA256

HTTP/2 is not negotiated

HTTP/2 provides multiplexing and header compression for better performance.

Got: http/1.1

OCSP stapling enabled

Certificate is valid (expires in 199 days)

Got: 2026-11-21T23:59:59Z

Certificate chain has 3 certificates

Certificate uses modern signature algorithm

Got: SHA256-RSA

Certificate covers 34 domain(s)

Got: zalando.com, zalando.ee, zalando.ch, zalando.com.tr, zalando.com.au, zalando.es, zalando.gr, zalando.it, zalando.se, *.zalando.com.tr, zalando.si, zalando.sk, *.zalando.com, zalando.ie, zalando.de, zalando.no, zalando.co.uk, *.zalando.com.au, zalando.bg, zalando.be, zalando.fi, zalando.pt, zalando.lu, zalando.hr, zalando.lv, zalando.dk, zalando.lt, zalando.hu, zalando.fr, zalando.at, zalando.cz, zalando.ro, zalando.nl, zalando.pl

Certificate is issued by a trusted CA

Got: CN=Amazon RSA 2048 M01,O=Amazon,C=US

HTTP/2 provides multiplexing and header compression for better performance.

Why this matters

HTTP/1.1 forces the browser to make sequential requests, multiplying latency on every page.

Learn more ▾

HTTP/2 (and HTTP/3) multiplex many requests over a single connection, eliminating head-of-line blocking. HTTP/1.1 forces the browser to either queue requests or open many parallel connections — both worse. Most modern web servers support HTTP/2 with one config line.

Source: MDN Web Docs

Connection

Protocol

TLS 1.3

Cipher Suite

TLS_AES_128_GCM_SHA256

HTTP Version

HTTP/1.1

Certificate Chain

Leaf Certificate

Subject CN=zalando.comIssuer CN=Amazon RSA 2048 M01,O=Amazon,C=USValid 2025-10-23T00:00:00Z → 2026-11-21T23:59:59ZExpires in 199 days SANs zalando.com, zalando.ee, zalando.ch, zalando.com.tr, zalando.com.au, zalando.es, zalando.gr, zalando.it, zalando.se, *.zalando.com.tr, zalando.si, zalando.sk, *.zalando.com, zalando.ie, zalando.de, zalando.no, zalando.co.uk, *.zalando.com.au, zalando.bg, zalando.be, zalando.fi, zalando.pt, zalando.lu, zalando.hr, zalando.lv, zalando.dk, zalando.lt, zalando.hu, zalando.fr, zalando.at, zalando.cz, zalando.ro, zalando.nl, zalando.plSignature SHA256-RSASerial 507a80409269fc86a8731c294c46b2a

Intermediate (CA Certificate)

Subject CN=Amazon RSA 2048 M01,O=Amazon,C=USIssuer CN=Amazon Root CA 1,O=Amazon,C=USValid 2022-08-23T22:21:28Z → 2030-08-23T22:21:28ZExpires in 1570 days Signature SHA256-RSASerial 77312380b9d6688a33b1ed9bf9ccda68e0e0f

Intermediate (CA Certificate)

Subject CN=Amazon Root CA 1,O=Amazon,C=USIssuer CN=Starfield Services Root Certificate Authority - G2,O=Starfield Technologies\, Inc.,L=Scottsdale,ST=Arizona,C=USValid 2015-05-25T12:00:00Z → 2037-12-31T01:00:00ZExpires in 4256 days Signature SHA256-RSASerial 67f944a2a27cdf3fac2ae2b01f908eeb9c4c6

A+

Cookie Security

No cookies set — no cookie security risks

PASS

No cookies set — no cookie security risks

No cookies detected — no cookie security risks to report.

A+

Subresource Integrity

No external resources

PASS

No external resources

No external resources to protect

SRI Coverage No external resources — SRI not applicable

A+

JS Library Vulnerabilities

No known vulnerabilities

PASS

No known vulnerabilities

No known JavaScript library vulnerabilities detected

No known JavaScript library vulnerabilities detected.

A+

Information Leakage

No exposures

PASS

No exposures

security.txt is present — good practice

No sensitive files exposed

No sensitive files exposed — all paths returned 404.

Path	Status	Category	Risk
/.git/HEAD	✓ Not found	Version Control	—
/.git/config	✓ Not found	Version Control	—
/.svn/entries	✓ Not found	Version Control	—
/.env	✓ Not found	Configuration	—
/.env.local	✓ Not found	Configuration	—
/.env.production	✓ Not found	Configuration	—
/wp-config.php	✓ Not found	Configuration	—
/.htaccess	✓ Not found	Configuration	—
/phpinfo.php	✓ Not found	Debug	—
/server-status	✓ Not found	Debug	—
/server-info	✓ Not found	Debug	—
/.well-known/security.txt	✗ Exposed	Security Policy	Info