FKIE_CVE-2026-10100

Vulnerability from fkie_nvd - Published: 2026-06-02 03:16 - Updated: 2026-06-02 13:03
Severity
4.4 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N
Summary
The Simple Custom Login Page plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the color settings fields (Page Background, Form Background, Text Color, Link Color) in versions up to and including 1.0.3. This is due to insufficient input sanitization of the color option values (they were registered with register_setting() and stored via the Settings API/update_option() with no sanitize_callback) combined with the values being output into a <style> block on wp-login.php using esc_attr(), which is incorrect for a CSS context (it does not escape ;, {, }, / or *). This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary CSS rules into the login page that are rendered for all unauthenticated visitors, enabling UI-redress and credential-phishing attacks.
References
security@wordfence.comhttps://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/admin/class-simple-custom-login-page-admin.php#L206
security@wordfence.comhttps://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/includes/class-simple-custom-login-page.php#L248
security@wordfence.comhttps://www.wordfence.com/threat-intel/vulnerabilities/id/96d03984-623a-44c7-a46f-e1aabbc566d5?source=cve
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Simple Custom Login Page plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the color settings fields (Page Background, Form Background, Text Color, Link Color) in versions up to and including 1.0.3. This is due to insufficient input sanitization of the color option values (they were registered with register_setting() and stored via the Settings API/update_option() with no sanitize_callback) combined with the values being output into a \u003cstyle\u003e block on wp-login.php using esc_attr(), which is incorrect for a CSS context (it does not escape ;, {, }, / or *). This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary CSS rules into the login page that are rendered for all unauthenticated visitors, enabling UI-redress and credential-phishing attacks."
    }
  ],
  "id": "CVE-2026-10100",
  "lastModified": "2026-06-02T13:03:31.153",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.4,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "HIGH",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.3,
        "impactScore": 2.7,
        "source": "security@wordfence.com",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-06-02T03:16:15.077",
  "references": [
    {
      "source": "security@wordfence.com",
      "url": "https://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/admin/class-simple-custom-login-page-admin.php#L206"
    },
    {
      "source": "security@wordfence.com",
      "url": "https://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/includes/class-simple-custom-login-page.php#L248"
    },
    {
      "source": "security@wordfence.com",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/96d03984-623a-44c7-a46f-e1aabbc566d5?source=cve"
    }
  ],
  "sourceIdentifier": "security@wordfence.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security@wordfence.com",
      "type": "Primary"
    }
  ]
}


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