BoletimSec•September 23, 2026•🇵🇹Translated from Portuguese

WordPress Patches Critical Core Vulnerability CVE-2026-87902 Affecting All Versions from 4.7.0

WordPress has issued security updates that address a critical vulnerability in the platform's core, identified as CVE-2026-87902 and rated CVSS 9.2. The flaw affects all versions from 4.7.0 to 7.1.1, leaving the vast majority of installations exposed until the latest patches are applied.

The vulnerability exists in the base code rather than in any plugin or theme. This means sites running a clean installation with no additional extensions are still at risk. An attacker can load a PHP file located outside the designated theme directories. Under specific server configurations, this capability can be leveraged to execute arbitrary code chosen by the attacker.

Exploitation requires no authentication and no interaction from any logged-in user, making the attack surface available to any visitor. The absence of required credentials significantly increases the severity of the issue.

Patch Releases

Security updates have been distributed across all currently supported branches:

  • 7.1.x → version 7.1.2
  • 7.0.x → version 7.0.6
  • 6.9.x → version 6.9.9
  • 6.8.x → version 6.8.10
  • 6.7.x → version 6.7.9
  • 6.6.x → version 6.6.9
  • Support extends back to 4.7.37

The vulnerability was reported in July by researcher Robert Ressl via a private disclosure on HackerOne and made public on 22 September. No evidence of active exploitation in the wild has been recorded to date.

Site owners are strongly advised to update immediately and ensure automatic updates remain enabled. For environments where immediate patching is not feasible, temporary mitigations include disabling register_argc_argv and removing unused PEAR components.

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