Cyber Posture

CVE-2026-22421

High

Published: 05 March 2026

Published
05 March 2026
Modified
22 April 2026
KEV Added
—
Patch
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CVSS Score 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0016 37.1th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Description

Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in AncoraThemes Quantum quantum allows PHP Local File Inclusion.This issue affects Quantum: from n/a through <= 1.0.

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match
prevent

SI-2 requires timely identification, reporting, and remediation of flaws, directly addressing the PHP local file inclusion vulnerability in the Quantum WordPress theme by applying patches or updates.

SI-10 Information Input Validation good match
prevent

SI-10 mandates information input validation and error handling, preventing exploitation of improper filename controls in PHP include/require statements used in this LFI vulnerability.

SI-9 Information Input Restrictions good match
prevent

SI-9 enforces restrictions on information inputs by type, pattern, or content, blocking malicious filenames supplied by unauthenticated attackers targeting the file inclusion mechanism.

Security SummaryAI

CVE-2026-22421 is an Improper Control of Filename for Include/Require Statement in PHP Program vulnerability, classified as PHP Remote File Inclusion but enabling PHP Local File Inclusion (CWE-98), in the Quantum WordPress theme developed by AncoraThemes. This issue affects all versions of the Quantum theme from n/a through 1.0 inclusive. The vulnerability was published on 2026-03-05 and carries a CVSS v3.1 base score of 8.1 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to network accessibility despite high attack complexity.

Unauthenticated remote attackers can exploit this vulnerability over the network without requiring user interaction. Exploitation allows high-impact compromise of confidentiality, integrity, and availability, typically through local file inclusion to access sensitive files or, in certain configurations, achieve remote code execution via PHP inclusion mechanisms.

Mitigation details are provided in the Patchstack advisory at https://patchstack.com/database/Wordpress/Theme/quantum/vulnerability/wordpress-quantum-theme-1-0-local-file-inclusion-vulnerability?_s_id=cve.

Details

CWE(s)
CWE-98

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.
attack.mitre.org →
Why these techniques?

Unauthenticated remote LFI vulnerability in a public-facing WordPress theme directly enables exploitation of a public-facing web application.

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

References