Security - https://joinmastodon.org BeaverCheck Audit

F

Subresource Integrity

Action

0 of 2 external resources have SRI

FIX

0 of 2 external resources have SRI

External script from scripts.simpleanalyticscdn.com lacks integrity attribute

Without SRI, if this CDN is compromised, attackers could inject malicious code.

Got: https://scripts.simpleanalyticscdn.com/latest.js

External script from scripts.simpleanalyticscdn.com lacks integrity attribute

Without SRI, if this CDN is compromised, attackers could inject malicious code.

Got: https://scripts.simpleanalyticscdn.com/auto-events.js

SRI Coverage 0 / 2 of external resources have integrity hashes

Tag	Domain	Integrity
<script>	scripts.simpleanalyticscdn.com	✗ Missing
<script>	scripts.simpleanalyticscdn.com	✗ Missing

D

security.txt

Action

No /.well-known/security.txt published

FIX

security.txt

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

B

Security Headers

6 of 10 headers properly configured

REVIEW

6 of 10 headers properly configured

Strict-Transport-Security is properly configured

Got: max-age=31536000; includeSubDomains; preload

X-Content-Type-Options is properly configured

Got: 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 has a weak value

Got: origin-when-cross-origin Expected: strict-origin-when-cross-origin

Permissions-Policy is set

Got: camera=(), microphone=(), geolocation=(), browsing-topics=()

Content-Security-Policy is present

Got: default-src 'self'; child-src 'self'; object-src 'none'; img-src 'self' proxy.jo…

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 not present

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

Expected: strict-origin-when-cross-origin

Why this matters

Weak Referrer-Policy values leak full URLs (with query params, tokens, IDs) to every third-party resource on the page.

Learn more ▾

Default referrer behavior shares the full referring URL with images, scripts, and other resources from third-party origins. If your URLs contain tokens, session IDs, or user emails (in query strings or paths), every third-party tracker gets them. Set `Referrer-Policy: strict-origin-when-cross-origin` (or stricter).

Source: MDN Referrer-Policy / 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

B

Content Security Policy

5 of 10 CSP checks passed

REVIEW

5 of 10 CSP checks passed

Raw CSP policy

Got: default-src 'self'; child-src 'self'; object-src 'none'; img-src 'self' proxy.joinmastodon.org blob: data: https://queue.simpleanalyticscdn.com https://simpleanalyticsbadges.com; style-src 'self' 'unsafe-inline'; script-src 'self' https://scripts.simpleanalyticscdn.com; connect-src 'self' api.joinmastodon.org https://queue.simpleanalyticscdn.com https://scripts.simpleanalyticscdn.com; block-all-mixed-content

default-src directive is set

Got: default-src 'self'

No 'unsafe-inline' in script source

No 'unsafe-eval' in script source

No wildcard in script source

object-src is set to 'none'

Got: object-src 'none'

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'

frame-ancestors directive is missing

frame-ancestors controls who can embed your page, preventing clickjacking. Set it to 'self' or 'none'.

Expected: frame-ancestors 'self'

form-action directive is missing

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

Expected: form-action 'self'

upgrade-insecure-requests is not set

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

Expected: upgrade-insecure-requests

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

frame-ancestors controls who can embed your page, preventing clickjacking. Set it to 'self' or 'none'.

Expected: frame-ancestors 'self'

Why this matters

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

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

default-src 'self'

child-src 'self'

object-src 'none'

img-src 'self'proxy.joinmastodon.orgblob:data:https://queue.simpleanalyticscdn.comhttps://simpleanalyticsbadges.com

style-src 'self''unsafe-inline'

script-src 'self'https://scripts.simpleanalyticscdn.com

connect-src 'self'api.joinmastodon.orghttps://queue.simpleanalyticscdn.comhttps://scripts.simpleanalyticscdn.com

block-all-mixed-content

B

Permissions-Policy

4 directives, 2 missing

REVIEW

4 directives, 2 missing

camera=() — blocked for all origins

microphone=() — blocked for all origins

geolocation=() — blocked for all origins

browsing-topics=() — blocked for all origins

payment not restricted

Consider adding payment=() to block payment access from embedded content.

usb not restricted

Consider adding usb=() to block usb access from embedded content.

Raw Header

camera=() microphone=() geolocation=() browsing-topics=()

Feature Permissions

Blocked Self Only Unrestricted Not Set

camera Blocked

microphone Blocked

geolocation Blocked

browsing-topics Blocked

payment Not Set

usb Not Set

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

A+

TLS & Certificates

TLS 1.3, 7 checks passed

PASS

TLS 1.3, 7 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

Certificate is valid (expires in 34 days)

Got: 2026-05-26T16:23:26Z

Certificate chain has 2 certificates

Certificate uses modern signature algorithm

Got: SHA256-RSA

Certificate covers 4 domain(s)

Got: api.joinmastodon.org, joinmastodon.org, proxy.joinmastodon.org, www.joinmastodon.org

Certificate is issued by a trusted CA

Got: CN=R12,O=Let's Encrypt,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=joinmastodon.orgIssuer CN=R12,O=Let's Encrypt,C=USValid 2026-02-25T16:23:27Z → 2026-05-26T16:23:26ZExpires in 34 days SANs api.joinmastodon.org, joinmastodon.org, proxy.joinmastodon.org, www.joinmastodon.orgSignature SHA256-RSASerial 6983a6aa3522805a96ec75cc1a5554f851e

Intermediate (CA Certificate)

Subject CN=R12,O=Let's Encrypt,C=USIssuer CN=ISRG Root X1,O=Internet Security Research Group,C=USValid 2024-03-13T00:00:00Z → 2027-03-12T23:59:59ZExpires in 325 days Signature SHA256-RSASerial c212324b70a9b49171dc40f7e285263c

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+

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

No security.txt found

Consider adding a security.txt at /.well-known/security.txt.

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	✓ Not found	Security Policy	—

A

Email Security

DMARC: quarantine

PASS

DMARC: quarantine

DMARC policy is quarantine — good protection

DMARC

Policy quarantine — good protection Record v=DMARC1; p=quarantine; pct=100; rua=mailto:re+o0lrkfqmq6a@dmarc.postmarkapp.com; sp=quarantine; aspf=r;

A+

Transport Security

HTTP/3, HSTS, and TLS version analysis

PASS

HTTP/3, HSTS, and TLS version analysis

HTTP/3 (QUIC) supported

The server advertises HTTP/3 via Alt-Svc for faster connections on mobile networks.

HSTS enabled (includeSubDomains, preload)

HSTS preload enabled

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