CVE-2026-81689

openssl_encrypt versions before 1.4.9 derive the remote-pepper wrap key using unsalted HKDF-SHA256 or bare SHA-256 of the password, allowing identical keys across all users and files. Attackers with access to wrapped pepper blobs can precompute a single dictionary table and perform fleet-wide offline password guessing at hardware speed to recover user passwords.

  • Published Aug 27, 2026
  • CVSS 8.7 high
  • 0.3% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-81689 at the National Vulnerability Database