CVE-2026-91827: CWE-502 Deserialization of Untrusted Data in Ninja Forms
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.
AI Analysis
Technical Summary
CVE-2026-91827 is a deserialization of untrusted data vulnerability (CWE-502) in Ninja Forms WordPress plugin version 3.15.3. The plugin does not prevent user-submitted form field values from being deserialized during CSV export of form submissions by an administrator. An unauthenticated attacker can exploit this to perform PHP Object Injection. If a suitable POP chain is available via other installed plugins or themes, this can lead to arbitrary file operations or remote code execution.
Potential Impact
Successful exploitation can result in high impact including confidentiality, integrity, and availability compromise. Specifically, it can lead to arbitrary file operations or remote code execution on the affected system. The vulnerability is exploitable without authentication but requires user interaction (administrator exporting data) and a suitable gadget chain in the environment.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, administrators should avoid exporting form submissions to CSV or restrict access to this functionality. Review installed plugins and themes for potential gadget chains that could be leveraged in exploitation.
CVE-2026-91827: CWE-502 Deserialization of Untrusted Data in Ninja Forms
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 v3.1
Score 7.5high
Affected software
Ninja Forms
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-91827 is a deserialization of untrusted data vulnerability (CWE-502) in Ninja Forms WordPress plugin version 3.15.3. The plugin does not prevent user-submitted form field values from being deserialized during CSV export of form submissions by an administrator. An unauthenticated attacker can exploit this to perform PHP Object Injection. If a suitable POP chain is available via other installed plugins or themes, this can lead to arbitrary file operations or remote code execution.
Potential Impact
Successful exploitation can result in high impact including confidentiality, integrity, and availability compromise. Specifically, it can lead to arbitrary file operations or remote code execution on the affected system. The vulnerability is exploitable without authentication but requires user interaction (administrator exporting data) and a suitable gadget chain in the environment.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, administrators should avoid exporting form submissions to CSV or restrict access to this functionality. Review installed plugins and themes for potential gadget chains that could be leveraged in exploitation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- WPScan
- Date Reserved
- 2026-09-15T08:07:50.100Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ab22bc3f7a7c54106d25063
Added to database: 09/22/2026, 07:18:27 UTC
Last enriched: 09/22/2026, 07:32:43 UTC
Last updated: 09/22/2026, 15:50:45 UTC
Views: 13
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.