CVE-2026-10100 (GCVE-0-2026-10100)
Vulnerability from cvelistv5 – Published: 2026-06-02 01:28 – Updated: 2026-06-02 10:48
VLAI
EPSS
VEX
Title
Simple Custom Login Page <= 1.0.3 - Authenticated (Admin+) Stored Cross-Site Scripting
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.
Severity
4.4 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-02 10:39 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
Wordfence
CNA
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| pattihis | Simple Custom Login Page |
Affected:
0 , ≤ 1.0.3
(semver)
|
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