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Security

· 13 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
71
GRADE
C
FIX
4
REVIEW
5
PASS
4
INFO
0
Checks
13
4 PASS 5 REVIEW 4 FIX
D
Security Headers
Action
4 of 10 headers properly configured
FIX
4 of 10 headers properly configured
Warning::
HSTS max-age is too short (15768000s, should be ≥ 31536000s)
A short max-age leaves a window for downgrade attacks. Set max-age to at least 31536000 (1 year).
Got: max-age=15768000 Expected: max-age=31536000; includeSubDomains
Info::
X-Content-Type-Options is properly configured
Got: nosniff
Info::
X-Frame-Options is properly configured
Got: SAMEORIGIN
Warning::
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
Warning::
Permissions-Policy header is missing
Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features.
Expected: geolocation=(), camera=(), microphone=()
Info::
Content-Security-Policy is present
Got: frame-ancestors 'self' https://*.erp.tu-dresden.de:* https://piwik.mz.tu-dresden…
Warning::
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
Warning::
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
Warning::
X-Powered-By header reveals technology stack
This header discloses server technology (e.g. Express, PHP), helping attackers target known vulnerabilities. Remove it.
Got: Zope (www.zope.dev), Python (www.python.org)
Info::
Server header is present without version info
Got: nginx

A short max-age leaves a window for downgrade attacks. Set max-age to at least 31536000 (1 year).

Expected: max-age=31536000; includeSubDomains
Why this matters

Short HSTS max-age leaves a downgrade-attack window every time the cache expires — set ≥ 1 year.

Learn more

max-age below 31536000 (1 year) is below industry recommendation. The browser forgets the HSTS policy and re-exposes first-visit downgrade attacks. Set to 63072000 (2 years) and add `includeSubDomains; preload` to qualify for the HSTS preload list.

Source: RFC 6797 / hstspreload.org

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

This header discloses server technology (e.g. Express, PHP), helping attackers target known vulnerabilities. Remove it.

Why this matters

X-Powered-By: PHP/7.4.3 advertises your stack to attackers — disable it.

Learn more

X-Powered-By and similar headers (X-AspNet-Version, X-Runtime) tell attackers which versions to target. Disable in your server/framework config: PHP `expose_php=Off`, ASP.NET `<httpRuntime enableVersionHeader="false">`, Express `app.disable('x-powered-by')`.

Source: OWASP

F
Subresource Integrity
Action
0 of 1 external resources have SRI
FIX
0 of 1 external resources have SRI
Warning::
External script from matomo.tu-dresden.de lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: //matomo.tu-dresden.de/matomo.js
SRI Coverage 0 / 1 of external resources have integrity hashes
TagDomainIntegrity
<script>matomo.tu-dresden.de Missing
D
Email Security
Action
DMARC: none
FIX
DMARC: none
Warning::
DMARC policy is none — monitoring only
This only monitors, it doesn't block spoofed emails. Change to p=quarantine or p=reject.
DMARC
Policy none — monitoring only, does not block spoofing Record v=DMARC1; p=none; rua=mailto:dmarcreports@zih.tu-dresden.de

This only monitors, it doesn't block spoofed emails. Change to p=quarantine or p=reject.

Why this matters

DMARC p=none collects reports but doesn't actually block spoofed mail — phishing emails still reach inboxes.

Learn more

DMARC's three policies are p=none (monitor only), p=quarantine (mark as spam), and p=reject (bounce). Most domains start at p=none to gather data, but stay there forever, leaving spoofers unblocked. After 30 days of clean DMARC reports, graduate to p=quarantine, then p=reject.

Source: DMARC.org / NIST

D
Permissions-Policy
Action
No header set
FIX
No header set
Warning::
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=()
B
Content Security Policy
2 of 10 CSP checks passed
REVIEW
2 of 10 CSP checks passed
Info::
Raw CSP policy
Got: frame-ancestors 'self' https://*.erp.tu-dresden.de:* https://piwik.mz.tu-dresden.de https://matomo.tu-dresden.de
Warning::
default-src directive is missing
default-src provides a fallback for other directives. Set it to restrict default resource loading.
Expected: default-src 'self'
Info::
No script-src or default-src to check for 'unsafe-inline'
Info::
No script-src or default-src to check for 'unsafe-eval'
Info::
No script-src or default-src to check for wildcard
Info::
object-src falls back to default-src
Warning::
base-uri directive is missing
Without base-uri, attackers can inject a <base> tag to hijack relative URLs. Set it to 'self' or 'none'.
Expected: base-uri 'self'
Info::
frame-ancestors directive is set
Got: frame-ancestors 'self' https://*.erp.tu-dresden.de:* https://piwik.mz.tu-dresden.de https://matomo.tu-dresden.de
Warning::
form-action directive is missing
form-action restricts where forms can submit data, preventing form hijacking.
Expected: form-action 'self'
Info::
upgrade-insecure-requests is not set
This directive upgrades HTTP resources to HTTPS automatically, preventing mixed content.
Expected: upgrade-insecure-requests

default-src provides a fallback for other directives. Set it to restrict default resource loading.

Expected: default-src 'self'
Why this matters

Security gaps expose your site and users to attacks, eroding trust.

Without base-uri, attackers can inject a <base> tag to hijack relative URLs. Set it to 'self' or 'none'.

Expected: base-uri 'self'
Why this matters

Missing base-uri in CSP leaves a base-tag injection attack path open even on otherwise strict policies.

Learn more

A common omission: developers add CSP for script-src and frame-ancestors but forget base-uri. The result is a CSP that looks strict but lets an attacker rewrite every URL on the page via <base href>. Add `base-uri 'self'` to close the gap.

Source: MDN CSP

form-action restricts where forms can submit data, preventing form hijacking.

Expected: form-action 'self'
Why this matters

Security gaps expose your site and users to attacks, eroding trust.

This directive upgrades HTTP resources to HTTPS automatically, preventing mixed content.

Expected: upgrade-insecure-requests
Why this matters

Without upgrade-insecure-requests, any HTTP subresource link survives as a mixed-content warning instead of auto-upgrading.

Learn more

Adding `upgrade-insecure-requests` to your CSP turns every http:// subresource fetch into https:// at the browser layer. One-line defense against accidental mixed content from legacy links or third-party widgets.

Source: MDN CSP

Parsed Policy

frame-ancestors 'self'https://*.erp.tu-dresden.de:*https://piwik.mz.tu-dresden.dehttps://matomo.tu-dresden.de
B
CORS Configuration
No CORS headers
REVIEW
No CORS headers
Info::
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
C
Known vulnerability matches
Action
2 known vulnerability match(es) against detected tech
REVIEW

Known Vulnerabilities

LibraryVersionSeveritySummaryFixed In
Underscore.js1.9.1high vulnerable to Arbitrary Code Injection via the template function1.12.1
Underscore.js1.9.1high### Impact In simple words, some programs that use `_.flatten` or `_.isEqual` could be made to crash. Someone who wants to do harm may be able to do this on purpose. This can only be done if the program has special properties. It only works in Underscore versions up to 1.13.7. A more detailed explanation follows. In affected versions of Underscore, the `_.flatten` and `_.isEqual` functions use recursion without a depth limit. Under very specific conditions, detailed below, an attacker could exploit this in a Denial of Service (DoS) attack by triggering a stack overflow. A proof of concept (PoC) for this type of attack with `_.isEqual`: ```js const _ = require('underscore'); // build JSON string for nested object ~4500 levels deep // (for this to be an attack, the JSON would have to come from // a request or other untrusted input) let json = ''; for (let i = 0; i < 4500; i++) json += '{"n":'; json += '"x"'; for (let i = 0; i < 4500; i++) json += '}'; // construct two distinct objects with equal shape from the above JSON const a = JSON.parse(json); const b = JSON.parse(json); _.isEqual(a, b); // RangeError: Maximum call stack size exceeded ``` A proof of concept (PoC) for this type of attack with `_.flatten`: ```js const _ = require('underscore'); // build nested array ~4500 levels deep // (like with _.isEqual, this nested array would have to be sourced // from an untrusted external source for it to be an attack) let nested = []; for (let i = 0; i < 4500; i++) nested = [nested]; _.flatten(nested); // RangeError: Maximum call stack size exceeded ``` An application that crashes because of this can be restarted, so the bug is most relevant to applications for which continued operation is important, such as server applications. Furthermore, an application is only vulnerable to this type of attack if ALL of the following conditions are met: - Untrusted input must be used to create a recursive datastructure, for example using `JSON.parse`, with no enforced depth limit. - The datastructure thus created must be passed to `_.flatten` or `_.isEqual`. - In the case of `_.flatten`, the vulnerability can only be exploited if it is possible for a remote client to prepare a datastructure that consists of arrays at all levels AND if no finite depth limit is passed as the second argument to `_.flatten`. - In the case of `_.isEqual`, the vulnerability can only be exploited if there exists a code path in which two distinct datastructures that were submitted by the same remote client are compared using `_.isEqual`. For example, if a client submits data that are stored in a database, and the same client can later submit another datastructure that is then compared to the data that were saved in the database previously, OR if a client submits a single request, but its data are parsed twice, creating two non-identical but equivalent datastructures that are then compared. - Exceptions originating from the call to `_.flatten` or `_.isEqual`, as a result of a stack overflow, are not being caught. All versions of Underscore up to and including 1.13.7 are affected by this weakness. ### Patches The problem has been patched in version 1.13.8. Upgrading to 1.13.8 or later completely prevents exploitation. **Note:** historically, there have been breaking changes in minor releases of Underscore, especially between versions 1.6 and 1.9. However, upgrading from version 1.9 or later to any later 1.x version should be feasible with little or no effort for all users. ### Workarounds A workaround that works for both functions is to enforce a depth limit on the datastructure that is created from untrusted input. A limit of 1000 levels should prevent attacks from being successful on most systems. In systems with highly constrained hardware, we recommend lower limits, for example 100 levels. Another possible workaround that only works for `_.flatten`, is to pass a second argument that limits the flattening depth to 1000 or less. ### References - https://github.com/jashkenas/underscore/issues/3011 - https://underscorejs.org/#1.13.8 - https://underscorejs.org/#flatten - https://underscorejs.org/#isEqual1.13.8
C
security.txt
Action
Expired (2025-03-25T00:00:00Z) — update Expires field
REVIEW

security.txt

Contact: mailto:cert@tu-dresden.de, mailto:d7devops@tu-dresden.de
Expires: 2025-03-25T00:00:00Z
Encryption: https://tu-dresden.de/cids/scd/ressourcen/dateien/cert/TUD-CERT.pem, https://tu-dresden.de/cids/scd/ressourcen/dateien/cert/TUD-CERT.asc
Policy: https://tu-dresden.de/.well-known/security.txt
B
Transport Security
HTTP/3, HSTS, and TLS version analysis
REVIEW
HTTP/3, HSTS, and TLS version analysis
Info::
HTTP/3 (QUIC) not advertised
HTTP/3 eliminates head-of-line blocking. If your CDN supports it, consider enabling it.
Warning::
HSTS max-age is short: 182 days
HSTS max-age should be at least 1 year (31536000 seconds).
Got: max-age=15768000 (expected 31536000)
Info::
HSTS missing includeSubDomains
Without includeSubDomains, HSTS only protects the exact domain.
Info::
TLS 1.3 in use (fastest handshake, 1-RTT)
A+
TLS & Certificates
TLS 1.3, 7 checks passed
PASS
TLS 1.3, 7 checks passed
Info::
TLS 1.3 is used
Got: TLS 1.3
Info::
Strong cipher suite is used
Got: TLS_AES_256_GCM_SHA384
Info::
HTTP/2 is not negotiated
HTTP/2 provides multiplexing and header compression for better performance.
Got: http/1.1
Info::
Certificate is valid (expires in 189 days)
Got: 2026-10-28T16:20:14Z
Info::
Certificate chain has 3 certificates
Info::
Certificate uses modern signature algorithm
Got: ECDSA-SHA384
Info::
Certificate covers 18 domain(s)
Got: tu-dresden.de, dresden-uni.eu, www.tud.de, weltoffenheit.tu-dresden.de, www.dresden-uni.eu, www.dresden-uni.net, www.tu-dresden.org, uni-dresden.de, dresden-uni.info, www.tu-dresden.de, www.uni-dresden.de, webrelaunch.tu-dresden.de, tu-dresden.org, www.dresden-uni.info, tud.de, dresden-uni.com, www.dresden-uni.com, dresden-uni.net
Info::
Certificate is issued by a trusted CA
Got: CN=GEANT TLS ECC 1,O=Hellenic Academic and Research Institutions CA,C=GR

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_256_GCM_SHA384
HTTP Version
HTTP/1.1

Certificate Chain

Leaf Certificate
Subject CN=tu-dresden.de,O=Technische Universitaet Dresden,ST=Sachsen,C=DEIssuer CN=GEANT TLS ECC 1,O=Hellenic Academic and Research Institutions CA,C=GRValid 2025-10-28T16:20:14Z → 2026-10-28T16:20:14ZExpires in 189 days SANs tu-dresden.de, dresden-uni.eu, www.tud.de, weltoffenheit.tu-dresden.de, www.dresden-uni.eu, www.dresden-uni.net, www.tu-dresden.org, uni-dresden.de, dresden-uni.info, www.tu-dresden.de, www.uni-dresden.de, webrelaunch.tu-dresden.de, tu-dresden.org, www.dresden-uni.info, tud.de, dresden-uni.com, www.dresden-uni.com, dresden-uni.netSignature ECDSA-SHA384Serial 58afacf8f7fff7bb874310d318a6f5a5
Intermediate (CA Certificate)
Subject CN=GEANT TLS ECC 1,O=Hellenic Academic and Research Institutions CA,C=GRIssuer CN=HARICA TLS ECC Root CA 2021,O=Hellenic Academic and Research Institutions CA,C=GRValid 2025-01-03T11:14:21Z → 2039-12-31T11:14:20ZExpires in 5001 days Signature ECDSA-SHA384Serial 42fddce1261607e1a5e6935a400161dd
Intermediate (CA Certificate)
Subject CN=HARICA TLS ECC Root CA 2021,O=Hellenic Academic and Research Institutions CA,C=GRIssuer CN=Hellenic Academic and Research Institutions ECC RootCA 2015,O=Hellenic Academic and Research Institutions Cert. Authority,L=Athens,C=GRValid 2021-09-02T07:44:37Z → 2029-08-31T07:44:36ZExpires in 1227 days Signature ECDSA-SHA384Serial 716027c8857a73542def516c1c2eeb0f
A+
Cookie Security
No cookies set — no cookie security risks
PASS
No cookies set — no cookie security risks
Info::
No cookies set — no cookie security risks

No cookies detected — no cookie security risks to report.

A+
JS Library Vulnerabilities
No known vulnerabilities
PASS
No known vulnerabilities
Info::
No known JavaScript library vulnerabilities detected

No known JavaScript library vulnerabilities detected.

A+
Information Leakage
No exposures
PASS
No exposures
Info::
security.txt is present — good practice
Info::
No sensitive files exposed

No sensitive files exposed — all paths returned 404.

PathStatusCategoryRisk
/.git/HEAD Not foundVersion Control
/.git/config Not foundVersion Control
/.svn/entries Not foundVersion Control
/.env Not foundConfiguration
/.env.local Not foundConfiguration
/.env.production Not foundConfiguration
/wp-config.php Not foundConfiguration
/.htaccess Not foundConfiguration
/phpinfo.php Not foundDebug
/server-status Not foundDebug
/server-info Not foundDebug
/.well-known/security.txt ExposedSecurity PolicyInfo
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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