CVE-2026-54163 — secure_headers: CSP directive injection via sandbox, plugin_types, and report_to when given untrusted input
secure_headers manages application of security headers with many safe defaults. Prior to 7.3.0, secure_headers builds the Content-Security-Policy value by stitching directives w…
Published: 2026-07-17 · CVSS: 4.7 · CVSS 3.1
secure_headers manages application of security headers with many safe defaults. Prior to 7.3.0, secure_headers builds the Content-Security-Policy value by stitching directives with ; separators, and build_sandbox_list_directive, build_media_type_list_directive, and build_report_to_directive interpolate caller-supplied strings without scrubbing ;, \r, or \n. When untrusted input reaches SecureHeaders.override_content_security_policy_directives or append APIs for :sandbox, :plugin_types, or :report_to, an attacker can inject a CSP directive such as script-src 'unsafe-inline' * before the legitimate script-src, enabling XSS reachability through these sinks or CSP report exfiltration. This issue is fixed in version 7.3.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7