CVE-2026-91827 Ninja Forms - Insecure Deserialization

Ninja Forms WordPress plugin 3.15.3 contains a PHP Object Injection caused by deserialization of user-submitted form field values during CSV export by administrators, letting unauthenticated attackers perform arbitrary file operations or remote code execution if a suitable POP chain exists.

CVSS base score 7.5 /10
High
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.30% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Insecure Deserialization
Impact
Remote Code Execution, File System Write
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Published
22 September 2026
Updated
15 October 2026
Weakness
CWE-502

Vendor fix

Update to the latest version of Ninja Forms.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

← All CVEs