CVE-2026-39579

Vulnerability

The B Blocks plugin for WordPress, in versions 2.0.31 and earlier, contains a privilege escalation vulnerability. The issue resides in insufficient access control or capability checks, allowing a user with contributor-level access to escalate their privileges to a higher level, such as administrator. This vulnerability does not require any unusual configuration beyond having the plugin installed and active.

Exploitation

An attacker must first obtain a contributor account on the target WordPress site, which can be achieved through registration (if enabled) or by compromising an existing low-privilege account. The attacker then sends crafted requests to the vulnerable plugin endpoint(s) to exploit the missing authorization checks, thereby escalating their role to a higher privileged one.

Impact

Successful exploitation allows the attacker to escalate from a contributor account to a higher privilege level, such as administrator. This gives the attacker full control over the WordPress site, including the ability to install malicious plugins, modify content, access sensitive data, and potentially compromise the underlying server.

Mitigation

The vulnerability is fixed in version 2.0.32 of the B Blocks plugin. Users should update to version 2.0.32 or later immediately. If unable to update, using a web application firewall (WAF) or the Patchstack mitigation rule is recommended until the update can be applied [1].