CVE-2026-81719

openssl_encrypt before 1.4.9 executes untrusted third-party plugins with insufficient controls: the plugin signature policy defaulted to WARN, so an unsigned/unverifiable non-built-in plugin was compiled and executed in the host process at import time, before the runtime sandbox is installed. The only default gate was an incomplete, bypassable AST denylist. If a user is induced to load an attacker's plugin, this results in arbitrary code execution with the privileges of the user running openssl_encrypt. Fixed in 1.4.9 by defaulting the signature policy to ENFORCE for non-built-in plugins.

  • Published Aug 27, 2026
  • CVSS 9.3 critical
  • 0.4% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-81719 at the National Vulnerability Database