High severity · published Sep 22, 2026
CVE-2026-91827
Ninja Forms 3.15.3 - Unauthenticated PHP Object Injection via CSV Export
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
The Ninja Forms WordPress plugin 3.15.3 does not prevent user-submitted form field values from being deserialised when an administrator later exports form submissions to CSV, allowing unauthenticated attackers to perform PHP Object Injection; if a suitable POP chain is present via another installed plugin or theme, this can lead to actions such as arbitrary file operations or remote code execution.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NF
Ninja Forms ·
3.15.3 before 3.15.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91827
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91827
wpscan.com
https://wpscan.com/vulnerability/7b279db2-92e0-4122-b5c6-aa12b7b01858/
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