Migration, Backup, Staging <= 0.9.123 - Unauthenticated Arbitrary File Upload

Summary

The Migration, Backup, Staging – WPvivid Backup & Migration plugin for WordPress is vulnerable to Unauthenticated Arbitrary File Upload in versions up to and including 0.9.123. This is due to improper error handling in the RSA decryption process combined with a lack of path sanitization when writing uploaded files. When the plugin fails to decrypt a session key using openssl_private_decrypt(), it does not terminate execution and instead passes the boolean false value to the phpseclib library's AES cipher initialization. The library treats this false value as a string of null bytes, allowing an attacker to encrypt a malicious payload using a predictable null-byte key. Additionally, the plugin accepts filenames from the decrypted payload without sanitization, enabling directory traversal to escape the protected backup directory. This makes it possible for unauthenticated attackers to upload arbitrary PHP files to publicly accessible directories and achieve Remote Code Execution via the wpvivid_action=send_to_site parameter.

Timeline

1. Feb 11, 2026, 5:30 AM UTCCVE published
2. Feb 11, 2026, 3:45 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Apr 8, 2026, 5:29 PM UTCRecord last updated
4. Oct 28, 2026EPSS reached 10%

   FIRST estimates at least a 10% chance of exploitation in the next 30 days

Affected versions

• wpvividplugins WPvivid — Backup, Migration & Staging

  through 0.9.123

References 20