Ninja Forms Plugin up to 3.15.3 on WordPress Export deserialization

CVSS Meta Temp Score
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CTI Interest Score
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6.7$0-$5k2.32+

Summaryinfo

A vulnerability, which was classified as critical, has been found in Ninja Forms Plugin up to 3.15.3. Affected by this vulnerability is an unknown functionality of the component Export. The manipulation leads to deserialization. This vulnerability is listed as CVE-2026-91827. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Ninja Forms Plugin up to 3.15.3 and classified as critical. This issue affects an unknown functionality of the component Export. The manipulation with an unknown input leads to a deserialization vulnerability. Using CWE to declare the problem leads to CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at wpscan.com. The identification of this vulnerability is CVE-2026-91827 since 09/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading to version 3.15.4 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (WPScan): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Ninja Forms Plugin 3.15.4

Timelineinfo

09/15/2026 CVE reserved
09/22/2026 +7 days Advisory disclosed
09/22/2026 +0 days VulDB entry created
09/22/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wpscan.com
Status: Confirmed

CVE: CVE-2026-91827 (🔒)
GCVE (CVE): GCVE-0-2026-91827
GCVE (VulDB): GCVE-100-408353

Entryinfo

Created: 09/22/2026 09:23
Changes: 09/22/2026 09:23 (64)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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