Ultra Addons for Contact Form 7 <= 3.5.51 - Authenticated (Editor+) PHP Object Injection
Strategic Overview
- Status
- Patched in 3.5.52
- Affected Plugin
- Ultra Addons for Contact Form 7
- Affected Version
<= 3.5.51- CVSS
- 6.6Medium
- Weakness type
- CWE-502 · Deserialization of Untrusted Data
- CVE
CVE-2026-96833
At a glance
CVE-2026-96833 is a medium-severity Deserialization of Untrusted Data vulnerability in the Ultra Addons for Contact Form 7 WordPress plugin, affecting versions <= 3.5.51. It carries a CVSS score of 6.6 (reachable over the network; high confidentiality, integrity, availability impact). Exploitation requires an authenticated account at Editor level or above. The issue is fixed in version 3.5.52; sites on affected versions should update now. Disclosed September 2026, reported by Ananda Dhakal.
Vulnerability Overview
The Ultra Addons for Contact Form 7 plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.5.51. This is due to deserialization of untrusted input. This makes it possible for authenticated attackers, with editor-level access and above, 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 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 Ultra Addons for Contact Form 7 <= 3.5.51 takes an account at Editor level or above. 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 Ultra Addons for Contact Form 7 the fix is 3.5.52: builds <= 3.5.51 are affected, anything from 3.5.52 onward is not.
Remediation
Update to version 3.5.52, or a newer patched version
How does WordSec protect against this?
An attacker needs Editor access first, so the firewall sees the attempt as traffic from a logged-in account: 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: Ultra Addons for Contact Form 7 3.5.52 closes this, and updating the plugin is the step that ends it.
- Firewall
- Scanner
- Alerts
External References
Related records
Other vulnerabilities in Ultra Addons for Contact Form 7
- 9.8CVE-2026-82901: Ultra Addons for Contact Form 7 Arbitrary File Upload
CVE-2026-82901 - 9.8CVE-2026-84750: Ultimate Addons… Arbitrary File Upload
CVE-2026-84750 - 9.8CVE-2022-47586: Ultimate Addons for Contact Form 7 SQL Injection
CVE-2022-47586 - 8.8CVE-2023-1615: Ultimate Addons for Contact Form 7 SQL Injection
CVE-2023-1615 - 8.8CVE-2023-30495: Ultimate Addons for Contact Form 7 SQL Injection
CVE-2023-30495 - 7.2CVE-2026-103999: Ultra Addons for Contact Form 7 <= 3.5.54 Stored XSS
CVE-2026-103999 - 7.2CVE-2026-65439: Ultimate Addons for Contact Form 7 Stored XSS
CVE-2026-65439 - 7.2CVE-2025-6212: Ultra Addons for Contact Form 7 3.5.11… Stored XSS
CVE-2025-6212
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C