Ajax Search Lite – Live Search & Filter <= 4.14.4 - Unauthenticated PHP Object Injection
Strategic Overview
- Status
- Patched in 4.14.5
- Affected Plugin
- Ajax Search Lite – Live Search & Filter
- Affected Version
<= 4.14.4- CVSS
- 8.1High
- Weakness type
- CWE-502 · Deserialization of Untrusted Data
- CVE
CVE-2026-28139
At a glance
CVE-2026-28139 is a high-severity Deserialization of Untrusted Data vulnerability in the Ajax Search Lite WordPress plugin, affecting versions <= 4.14.4. It carries a CVSS score of 8.1 (reachable over the network; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 4.14.5; sites on affected versions should update now. Disclosed August 2026, reported by hhhai.
Vulnerability Overview
The Ajax Search Lite – Live Search & Filter plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 4.14.4 via deserialization of untrusted input. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-502: Deserialization of Untrusted Data
Reaching this weakness in Ajax Search Lite <= 4.14.4 takes no account at all. Deserialization of untrusted data means the application reconstructs objects from input a caller controls, letting the attacker choose which classes get instantiated and what their properties hold.
A workable chain turns deserialization into file writes, deletions or code execution, depending on what the loaded classes do in their magic methods. For Ajax Search Lite the fix is 4.14.5: builds <= 4.14.4 are affected, anything from 4.14.5 onward is not.
Remediation
Update to version 4.14.5, or a newer patched version
How does WordSec protect against this?
Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: Ajax Search Lite 4.14.5 closes this, and updating the plugin is the step that ends it.
- Firewall
- Scanner
- Login Security
External References
Related records
Other vulnerabilities in Ajax Search Lite – Live Search & Filter
- 9.8CVE-2014-4663: Ajax Search Lite < 3.11 Remote Code Execution
CVE-2014-4663 - 8.8Ajax Search Lite < 3.11 Remote Code Execution
- 7.2CVE-2023-1420: Ajax Search Lite <= 4.11 Reflected Cross-Site Scripting
CVE-2023-1420 - 6.1CVE-2024-21752: Ajax Search Lite <= 4.11.4 Reflected XSS
CVE-2024-21752 - 5.5CVE-2024-7084: Ajax Search Lite < 4.12 Stored Cross-Site Scripting
CVE-2024-7084 - 5.3CVE-2025-7956: Ajax Search Lite Unauthenticated Basic Information
CVE-2025-7956 - 4.4CVE-2024-13585: Ajax Search Lite <= 4.12.4 Stored Cross-Site Scripting
CVE-2024-13585 - 4.4CVE-2024-10568: Ajax Search Lite <= 4.12.3 Stored Cross-Site Scripting
CVE-2024-10568
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C