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Standard

Content Security Policy

A W3C browser standard that lets sites specify, via HTTP header or meta tag, which script, style, and resource sources a page may load, to curb XSS.

Known aliases

  • connect-src
  • connect-src 'self'
  • Content-Security-Policy
  • Content-Security-Policy-Report-Only
  • CSP
  • frame-ancestors
  • script-src
  • strict-dynamic

Current stories

buildOne report1 publisher

An <object> tag turns an uploaded SVG into stored XSS for every visitor

OopsSec Store, a deliberately vulnerable Next.js app, lets an admin-uploaded SVG run JavaScript in every visitor's browser. It works because the server trusts the client-set Content-Type and the product page renders SVGs through an <object> tag.

Publishers:dev.to

Reality

Evidence62
Adoption
Insufficient
Hype gap+8
Incentives40
Confidence72
securityConfirmed3 publishers

Attackers rewrote Brevo's embedded scripts at Cloudflare's edge with a hardcoded full-permission key

Brevo says a long-lived Cloudflare key with full account permissions sat in its application source code, and the Worker built with it stripped Content-Security-Policy headers from scripts that Sansec estimates reach 100,000 sites.

Perspective Coverage

3 publishers
Builder
Builder 34%
Operator
Operator 48%
Investor
Investor 18%

Reality

Evidence78
Adoption60
Hype gap+20
Incentives58
Confidence72
buildOne report1 publisher

A CSP directive turns every string passed to innerHTML into a TypeError

MDN now lists the Trusted Types API as Baseline 2026, newly available. The JavaScript half only lets you sanitize; require-trusted-types-for is the part that makes an unsanitized assignment throw, and the sanitizer stays yours to write.

Publishers:developer.mozilla.org

Reality

Evidence70
Adoption
Insufficient
Hype gap+8
Incentives22
Confidence63