CVE-2026-10100
Simple Custom Login Page <= 1.0.3 - Authenticated (Admin+) Stored Cross-Site Scripting
- 4.4MediumCVSS base score
- 0.18%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Wordfence
- 4 days later
· 4 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WordfenceCNA (assigner) | 3.1 | Medium4.4 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium4.4 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Affected products
pattihis · Simple Custom Login Page
- affected ≤ 1.0.3
References
References3
- https://www.wordfence.com/threat-intel/vulnerabilities/id/96d03984-623a-44c7-a46f-e1aabbc566d5?source=cve (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/includes/class-simple-custom-login-page.php#L248 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/simple-custom-login-page/tags/1.0.3/admin/class-simple-custom-login-page-admin.php#L206 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-33870 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-10100)Record last updated .