# CVE-2026-2890: Formidable Forms <= 6.28 - Missing Authorization to Unauthenticated Payment Integrity Bypass via PaymentIntent Reuse

> Unauthenticated attackers can bypass payment verification by reusing low-value Stripe PaymentIntents to mark high-value orders as complete.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Mar 2026
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-4rrh-wqqx-4jh2

## What is CVE-2026-2890?

CVE-2026-2890 is a high-severity missing authorization vulnerability in strategy11team Formidable Forms – Contact Form Plugin, Survey, Quiz, Payment, Calculator Form & Custom Form Builder, published on 13 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Formidable Forms plugin for WordPress is vulnerable to a payment integrity bypass in all versions up to, and including, 6.28. This is due to the Stripe Link return handler (`handle_one_time_stripe_link_return_url`) marking payment records as complete based solely on the Stripe PaymentIntent status without comparing the intent's charged amount against the expected payment amount, and the `verify_intent()` function validating only client secret ownership without binding intents to specific forms or actions. This makes it possible for unauthenticated attackers to reuse a PaymentIntent from a completed low-value payment to mark a high-value payment as complete, effectively bypassing payment for goods or services.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-2890?


## How do I fix CVE-2026-2890?

No fix has been published for CVE-2026-2890 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-2890 being exploited?

There is no known exploitation of CVE-2026-2890 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-2890 and fix it if it is affected.

What it is: CVE-2026-2890 is a high-severity missing authorization vulnerability in strategy11team Formidable Forms – Contact Form Plugin, Survey, Quiz, Payment, Calculator Form & Custom Form Builder, published on 13 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-2890 in the wild and no public exploit code.

Affected product: strategy11team Formidable Forms – Contact Form Plugin, Survey, Quiz, Payment, Calculator Form & Custom Form Builder. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-2890/ (Markdown: https://insights.sbomify.com/CVE-2026-2890/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-2890
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-2890
- OSV: https://osv.dev/vulnerability/CVE-2026-2890

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-2890/
Summaries are generated and may contain mistakes; the official description above is the record.