CVE-2026-54163: secure_headers: CSP directive injection via sandbox, plugin_types, and report_to when given untrusted input
Description
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.
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N · CWE-113, CWE-79
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
github: secure_headers
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/github/secure_headers/commit/286a79dea80c6a9be4ca93e0f284c923cf77e539 (opens in new tab)
- github.com/github/secure_headers/releases/tag/v7.3.0 (opens in new tab)
- github.com/github/secure_headers/security/advisories/GHSA-rqq5-2gf9-4w4q (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)