Cyber Resilience

CVE-2026-27986

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-2026-27986 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-2026-27986 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, affecting the ThemeREX OsTende WordPress theme in versions from n/a through 1.4.3. Published on 2026-03-05, it 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) and maps to CWE-98.

Unauthenticated remote attackers can exploit this vulnerability over the network, requiring high attack complexity but no user interaction or privileges. Successful exploitation grants high-impact access to confidentiality, integrity, and availability, allowing inclusion and potential execution of local files on the affected server.

The Patchstack advisory provides details on this Local File Inclusion vulnerability in the OsTende WordPress theme version 1.4.3, available at https://patchstack.com/database/Wordpress/Theme/ostende/vulnerability/wordpress-ostende-theme-1-4-3-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 OsTende ostende allows PHP Local File Inclusion.This issue affects OsTende: from n/a through <= 1.4.3.

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 a remote file inclusion flaw in a public-facing WordPress theme, directly enabling exploitation of a public-facing application.

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 specific flaw in the OsTende WordPress theme's PHP include/require handling, preventing exploitation of CVE-2026-27986.

prevent

Validates user-supplied inputs at web interfaces to ensure filenames used in PHP include/require statements cannot include arbitrary local files.

prevent

Enforces restrictive PHP configuration settings like open_basedir and disabled allow_url_include to limit the scope of local file inclusion even if input validation fails.

References