CVE-2026-49109: Salesforce Integration Auth Bypass Flaw

CVE-2026-49109 Overview

CVE-2026-49109 is an unauthenticated PHP Object Injection vulnerability in the WordPress plugin Integration for Salesforce and Contact Form 7, WPForms, Elementor, Formidable, Ninja Forms. The flaw affects all plugin versions up to and including 1.4.3. The vulnerability is categorized under [CWE-502: Deserialization of Untrusted Data]. An unauthenticated attacker can submit crafted serialized payloads over the network to trigger object instantiation inside the plugin. When combined with a usable POP (Property-Oriented Programming) gadget chain present in WordPress core, the plugin, or other installed plugins, exploitation can lead to remote code execution, arbitrary file operations, or sensitive data disclosure.

Critical Impact
Unauthenticated attackers can trigger PHP object deserialization remotely, enabling code execution or full site compromise when a suitable gadget chain exists.

Affected Products

Integration for Salesforce and Contact Form 7, WPForms, Elementor, Formidable, Ninja Forms — versions <= 1.4.3
WordPress sites running the vulnerable plugin (slug: cf7-salesforce)
Any environment where the plugin processes untrusted form submission data

Discovery Timeline

2026-06-15 - CVE-2026-49109 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2026-49109

Vulnerability Analysis

The plugin passes attacker-controlled input to a PHP deserialization sink (such as unserialize()) without validating or restricting the allowed classes. Because the entry point does not require authentication, any anonymous user submitting data through the plugin's integration endpoints can supply a serialized PHP object. PHP then instantiates the object and invokes magic methods such as __wakeup(), __destruct(), or __toString() during processing. If a POP gadget chain is reachable in the loaded codebase, the attacker can pivot from object instantiation to arbitrary file writes, SQL operations, or command execution. The Patchstack advisory confirms the issue as an unauthenticated PHP Object Injection affecting all versions through 1.4.3.

Root Cause

The root cause is unsafe deserialization of untrusted input [CWE-502]. The plugin treats serialized data received from form submissions or integration callbacks as trusted and feeds it directly into PHP's deserialization routines. No class allow-list, integrity check, or signed payload mechanism is enforced, so the deserializer accepts arbitrary object graphs.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker sends an HTTP request to a plugin endpoint that handles form input destined for Salesforce integration. The request body or a parameter contains a serialized PHP object crafted to abuse a gadget chain. When the server deserializes the payload, the chained magic methods execute, achieving the attacker's objective. Refer to the Patchstack Vulnerability Report for advisory details.

Detection Methods for CVE-2026-49109

Indicators of Compromise

Inbound HTTP requests to plugin endpoints containing serialized PHP markers such as O:, a:, s:, or C: patterns in POST bodies or query strings.
Unexpected outbound network connections, new PHP files in wp-content/uploads/, or modifications to WordPress core and plugin files.
New or modified WordPress administrator accounts and unexpected scheduled tasks (wp_cron entries) created shortly after suspicious form submissions.
PHP error log entries referencing __wakeup, __destruct, or class instantiation failures originating from the cf7-salesforce plugin path.

Detection Strategies

Inspect web server and WAF logs for serialized object syntax in requests targeting the plugin's AJAX or REST routes.
Hash and baseline plugin and theme files, then alert on any unauthorized modification.
Correlate anonymous POST submissions with subsequent PHP process spawning (sh, bash, curl, wget) on the host.

Monitoring Recommendations

Enable verbose logging on the WordPress site and forward web, PHP-FPM, and authentication logs to a centralized analytics platform for correlation.
Monitor for outbound connections from the web server to unfamiliar IPs immediately after form submission events.
Alert on creation of administrative users, plugin installations, and option changes in wp_options outside of approved maintenance windows.

How to Mitigate CVE-2026-49109

Immediate Actions Required

Update the Integration for Salesforce and Contact Form 7, WPForms, Elementor, Formidable, Ninja Forms plugin to a version newer than 1.4.3 as soon as a fixed release is available from the vendor.
If no patched version is available, deactivate and remove the plugin from all WordPress installations until a fix is published.
Audit affected sites for indicators of compromise, including unauthorized administrator accounts, modified files, and suspicious scheduled tasks.
Rotate WordPress administrator credentials, API keys, and Salesforce integration secrets used by the plugin.

Patch Information

A fixed version was not listed in the NVD entry at the time of publication. Consult the Patchstack Vulnerability Report and the vendor's plugin page for the latest patched release. Apply the update across all environments, including staging and disaster-recovery copies.

Workarounds

Deploy a web application firewall rule that blocks requests containing PHP serialization markers (O:<digit>:, C:<digit>:) on plugin endpoints.
Restrict access to plugin AJAX and REST routes by IP allow-list where business requirements permit.
Run PHP with the phar.readonly=On and disable risky functions (exec, system, passthru, proc_open) via disable_functions in php.ini to reduce gadget-chain impact.
Apply least-privilege file system permissions so the web server account cannot modify plugin or core files.

bash

# Example WAF rule (ModSecurity) to block PHP serialized payloads on plugin routes
SecRule REQUEST_URI "@contains /wp-content/plugins/cf7-salesforce/" \
  "chain,id:1049109,phase:2,deny,status:403,log,msg:'Blocked PHP Object Injection attempt - CVE-2026-49109'"
  SecRule REQUEST_BODY|ARGS "@rx (?:^|[^a-zA-Z0-9])(O|C):[0-9]+:\"[a-zA-Z_\\\\]+\":[0-9]+:\{" \
    "t:none"