CVE-2026-27369
Published: 05 March 2026
Summary
CVE-2026-27369 is a high-severity Deserialization of Untrusted Data (CWE-502) 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 18.1th 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).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly mitigates CVE-2026-27369 by requiring timely patching of the vulnerable BoldThemes Celeste WordPress theme to versions beyond 1.3.6, eliminating the deserialization flaw.
Prevents object injection by enforcing validation and sanitization of untrusted data before deserialization in the Celeste theme.
Identifies the presence of the vulnerable Celeste theme through vulnerability scanning, enabling proactive remediation of CVE-2026-27369.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Unauthenticated remote PHP object injection (deserialization) in a public-facing WordPress theme directly maps to exploitation of public-facing applications (T1190). Successful exploitation with available gadget chains commonly results in arbitrary code execution or web shell deployment on the server (T1505.003).
NVD Description
Deserialization of Untrusted Data vulnerability in BoldThemes Celeste celeste allows Object Injection.This issue affects Celeste: from n/a through <= 1.3.6.
Deeper analysisAI
CVE-2026-27369 is a Deserialization of Untrusted Data vulnerability (CWE-502) in the BoldThemes Celeste WordPress theme, enabling Object Injection. The issue affects Celeste versions from n/a through 1.3.6, as disclosed on 2026-03-05.
The vulnerability 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). Remote unauthenticated attackers can exploit it over the network with high attack complexity and no user interaction, potentially achieving high impacts on confidentiality, integrity, and availability through object injection.
Mitigation details are available in the Patchstack advisory at https://patchstack.com/database/Wordpress/Theme/celeste/vulnerability/wordpress-celeste-theme-1-3-6-php-object-injection-vulnerability?_s_id=cve.
Details
- CWE(s)