CVE-2026-102435

Ultra Addons for Contact Form 7 <= 3.5.54 - Unauthenticated PHP Object Injection to Arbitrary File Deletion via CF7 Form Field

2026-11-02 07:07
Sawyer

Strategic Overview

Status
Patched in 3.5.55
Affected Plugin
Ultra Addons for Contact Form 7
Affected Version
<= 3.5.54
CVSS
9.8Critical
Weakness type
CWE-502 · Deserialization of Untrusted Data
CVE
CVE-2026-102435
View all Ultra Addons for Contact Form 7 vulnerabilities

At a glance

CVE-2026-102435 is a critical-severity Deserialization of Untrusted Data vulnerability in the Ultra Addons for Contact Form 7 WordPress plugin, affecting versions <= 3.5.54. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 3.5.55; sites on affected versions should update now. Disclosed November 2026, reported by Sawyer.

Vulnerability Overview

The Ultra Addons for Contact Form 7 plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the _getObjAttr function in all versions up to, and including, 3.5.54. This makes it possible for unauthenticated attackers to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). This requires the PDF Generator add-on to be active and a Contact Form 7 form to be configured for PDF generation, as the WPCF7_Submission POP gadget chain relies on CF7 being present to complete the file deletion via __destruct(). Note: This vulnerability can only be exploited when the PDF generator feature is enabled.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, 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

Ultra Addons for Contact Form 7 <= 3.5.54 carries this weakness at __destruct(), and reaching it 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 Ultra Addons for Contact Form 7 the fix is 3.5.55: builds <= 3.5.54 are affected, anything from 3.5.55 onward is not.

Remediation

Update to version 3.5.55, 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: Ultra Addons for Contact Form 7 3.5.55 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Scanner
  • Login Security

External References

https://www.cve.org/CVERecord?id=CVE-2026-102435https://www.wordfence.com/threat-intel/vulnerabilities/id/187777a4-3438-489c-ad3b-7e16753189d6https://nvd.nist.gov/vuln/detail/CVE-2026-102435

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C