CVE-2026-27986
Published: 05 March 2026
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
- 🇪🇺 ENISA EUVD: EUVD-2026-9656
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
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.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly remediates the specific flaw in the OsTende WordPress theme's PHP include/require handling, preventing exploitation of CVE-2026-27986.
Validates user-supplied inputs at web interfaces to ensure filenames used in PHP include/require statements cannot include arbitrary local files.
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.