Ninja Forms: External Control of Assumed-Immutable Web Parameter
CVE-2026-65052 is a high-severity external control of assumed-immutable web parameter vulnerability in Ninja Forms from Saturday Drive, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 3.14.9 as the first without the flaw, so updating Ninja Forms to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.58% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Ninja Forms to 3.14.9 or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Saturday Drive | Ninja Forms | before 3.14.9 | 3.14.9 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.5 | High | CNA (vulncheck.com) |
Official description
Ninja Forms WordPress plugin version 3.14.8 and prior contains an improper input validation vulnerability that allows unauthenticated attackers to inject arbitrary numeric values into form calculations and payment totals by submitting values that do not match any configured option in ListSelect or ListRadio fields. Attackers can tamper with form submission payloads to the ajax submit endpoint, causing the get_calc_value() method to fail open and return attacker-controlled values, enabling manipulation of payment amounts to zero or arbitrary figures and bypassing admin-configured pricing logic.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: External Control of Assumed-Immutable Web Parameter
The web application does not sufficiently verify inputs that are assumed to be immutable but are actually externally controllable, such as hidden form fields.
How developers prevent this class of flaw
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
More External Control of Assumed-Immutable Web Parameter vulnerabilities (CWE-472)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Other vulnerabilities in Ninja Forms
- 7.1 High severity
- 9.3 Critical severity
- 9.3 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
Recent External Control of Assumed-Immutable Web Parameter vulnerabilities
- 8.3 High severity
- 9.6 Critical severity
- 8.1 High severity
- 8.8 High severity
- 8.3 High severity
- 8.3 High severity
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