Block For Mailchimp – Easy Mailchimp Form Integration <= 1.1.12 - Unauthenticated Blind Server-Side Request Forgery
Strategic Overview
- Status
- Patched in 1.1.13
- Affected Plugin
- Block for Mailchimp – grow your email list with signup forms
- Affected Version
<= 1.1.12- CVSS
- 4.0Medium
- Weakness type
- CWE-918 · Server-Side Request Forgery (SSRF)
- CVE
CVE-2025-10735
At a glance
CVE-2025-10735 is a medium-severity Server-Side Request Forgery (SSRF) vulnerability in the Block for Mailchimp WordPress plugin, affecting versions <= 1.1.12. It carries a CVSS score of 4.0 (reachable over the network). Exploitation requires no authentication. The issue is fixed in version 1.1.13; sites on affected versions should update now. Disclosed September 2025, reported by D01EXPLOIT OFFICIAL.
Vulnerability Overview
The Block For Mailchimp – Easy Mailchimp Form Integration plugin for WordPress is vulnerable to Blind Server-Side Request Forgery in all versions up to, and including, 1.1.12 via the mcbSubmit_Form_Data(). This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.
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.
CWE-918: Server-Side Request Forgery (SSRF)
Block for Mailchimp <= 1.1.12 carries this weakness at mcbSubmit_Form_Data(), and reaching it takes no account at all. Server-side request forgery means the application fetches a URL supplied by the caller, turning the server into a proxy for requests the attacker could not make directly.
The request originates from inside the hosting network, which is how these flaws reach cloud metadata endpoints, internal admin panels and services that trust local traffic. For Block for Mailchimp the fix is 1.1.13: builds <= 1.1.12 are affected, anything from 1.1.13 onward is not.
Remediation
Update to version 1.1.13, 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. None of that substitutes for the fix: Block for Mailchimp 1.1.13 closes this, and updating the plugin is the step that ends it.
- Firewall
- Login Security
- Alerts
External References
Related records
Other vulnerabilities in Block for Mailchimp – grow your email list with signup forms
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