Cyber Resilience

CVE-2026-28027

High

Published: 05 March 2026

Published
05 March 2026
Modified
22 April 2026
KEV Added
Patch
CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0040 32.0th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-28027 is a high-severity PHP Remote File Inclusion (CWE-98) vulnerability. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 32.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Deeper analysis

CVE-2026-28027 is an Improper Control of Filename for Include/Require Statement in PHP Program, classified as a PHP Remote File Inclusion vulnerability, in the ThemeREX Kayon WordPress theme. It enables PHP Local File Inclusion and affects Kayon versions from n/a through 1.3.

The vulnerability is exploitable over the network (AV:N) by unauthenticated attackers (PR:N) with no user interaction required (UI:N), though it involves high attack complexity (AC:H). Successful exploitation results in high impacts to confidentiality, integrity, and availability (C:H/I:H/A:H) within unchanged scope (S:U), yielding a CVSS v3.1 base score of 8.1.

Patchstack documents this Local File Inclusion vulnerability in the WordPress Kayon theme version 1.3 at https://patchstack.com/database/Wordpress/Theme/kayon/vulnerability/wordpress-kayon-theme-1-3-local-file-inclusion-vulnerability?_s_id=cve.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in ThemeREX Kayon kayon allows PHP Local File Inclusion.This issue affects Kayon: from n/a through <= 1.3.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The vulnerability is an LFI/RFI in a public-facing WordPress theme exploitable remotely without authentication, directly enabling exploitation of public-facing applications.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-58923Shared CWE-98
CVE-2025-69057Shared CWE-98
CVE-2024-54263Shared CWE-98
CVE-2026-28035Shared CWE-98
CVE-2026-28024Shared CWE-98
CVE-2025-67525Shared CWE-98
CVE-2025-22707Shared CWE-98
CVE-2025-69375Shared CWE-98
CVE-2026-22443Shared CWE-98
CVE-2025-53198Shared CWE-98

Affected Assets

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly remediates the improper filename control flaw in the Kayon theme's PHP include/require statements by identifying, reporting, and patching vulnerable versions <=1.3.

prevent

Validates user-supplied filenames for PHP include/require to prevent local file inclusion by ensuring only safe, authorized paths are processed.

prevent

Restricts filenames input to PHP include/require statements to a whitelist of allowed values, blocking directory traversal sequences used in local file inclusion exploits.

References