SECURELYN

CVE-2026-1357

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 a…

Scores

9.8
CVSS 9.8 out of 10, critical severity.
35.1%
EPSS 35.1% chance of exploitation in the next 30 days.

The facts

Published
11 February 2026
Last changed
17 June 2026
NVD status
Deferred
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
35.1% chance of exploitation activity in the next 30 days (percentile 98).

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References