# CVE-2026-54163: secure_headers: CSP directive injection via sandbox, plugin_types, and report_to when given untrusted input

> CVE-2026-54163: secure_headers: CSP directive injection via sandbox, plugin_types, and report_to when given untrusted input. CVSS 4.7 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-54163
Last updated: 2026-10-24T20:10:00Z

- Published: 2026-07-17 20:19 UTC · Updated: 2026-10-24 20:10 UTC · Assigner: GitHub\_M
- CVSS: 4.7 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS: 0.21%, 12th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-113, CWE-79

## 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.

## Affected vendors and products

- github: secure\_headers

## Tracked companies

- [GitHub](https://rewindex.com/company/github.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-54163)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-54163)
- [https://github.com/github/secure\_headers/commit/286a79dea80c6a9be4ca93e0f284c923cf77e539](https://github.com/github/secure_headers/commit/286a79dea80c6a9be4ca93e0f284c923cf77e539)
- [https://github.com/github/secure\_headers/releases/tag/v7.3.0](https://github.com/github/secure_headers/releases/tag/v7.3.0)
- [https://github.com/github/secure\_headers/security/advisories/GHSA-rqq5-2gf9-4w4q](https://github.com/github/secure_headers/security/advisories/GHSA-rqq5-2gf9-4w4q)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-54163 · Markdown: https://rewindex.com/cve/CVE-2026-54163.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-54163 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:13:21.416Z