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CVE-2026-54163

Full vulnerability record from the local CVENow database.

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.

Severity
MEDIUM
CVSS score
4.7 (v3.1)
Vulnerability status
Deferred
Source identifier
Published
2026-07-17 21:17:08.107000
Last modified
2026-10-24 20:10:00.137000
View original CVE JSON
{
  "id": "CVE-2026-54163",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-17T21:17:08.107",
  "lastModified": "2026-10-24T20:10:00.137",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "secure_headers gestiona la aplicación de encabezados de seguridad con muchos valores predeterminados seguros. Antes de la versión 7.3.0, secure_headers construye el valor de Content-Security-Policy uniendo directivas con separadores ;, y build_sandbox_list_directive, build_media_type_list_directive y build_report_to_directive interpolan cadenas proporcionadas por el llamador sin limpiar ;, \\r, o \\n. Cuando una entrada no confiable llega a SecureHeaders.override_content_security_policy_directives o a las API de adición para :sandbox, :plugin_types o :report_to, un atacante puede inyectar una directiva CSP como script-src ’unsafe-inline’ * antes del script-src legítimo, permitiendo la alcanzabilidad de XSS a través de estos sumideros o la exfiltración de informes CSP. Este problema está solucionado en la versión 7.3.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "github",
          "product": "secure_headers",
          "versions": [
            {
              "version": "< 7.3.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 2.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-20T17:45:32.192836Z",
          "id": "CVE-2026-54163",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        },
        {
          "lang": "en",
          "value": "CWE-113"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/github/secure_headers/commit/286a79dea80c6a9be4ca93e0f284c923cf77e539",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/github/secure_headers/releases/tag/v7.3.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/github/secure_headers/security/advisories/GHSA-rqq5-2gf9-4w4q",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/github/secure_headers/security/advisories/GHSA-rqq5-2gf9-4w4q",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}