# CVE-2026-66002: Frappe: User Enumeration via PDDR

> Remote attackers can enumerate registered users by analyzing response differences in public data request forms, exposing user existence.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Aug 2026
- **Updated:** 21 Aug 2026
- **Also known as:** GHSA-c2xv-c53h-qvr5

## What is CVE-2026-66002?

CVE-2026-66002 is a medium-severity vulnerability in frappe, published on 20 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Frappe is a full-stack web application framework. Prior to 15.115.0 and 16.27.0, the public request-data web form and PersonalDataDownloadRequest class in frappe/website/doctype/personal_data_download_request/personal_data_download_request.py return distinguishable response shapes for registered and unregistered email addresses, including the user_name field and persistence behavior. A remote attacker can compare the responses to enumerate registered users. This issue is fixed in versions 15.115.0 and 16.27.0.

Weakness: CWE-204 (Observable Response Discrepancy)

## Which versions are affected by CVE-2026-66002?


## How do I fix CVE-2026-66002?

No fix has been published for CVE-2026-66002 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-66002 being exploited?

There is no known exploitation of CVE-2026-66002 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-66002 and fix it if it is affected.

What it is: CVE-2026-66002 is a medium-severity vulnerability in frappe, published on 20 Aug 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-2026-66002 in the wild and no public exploit code.

Affected product: frappe. 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-2026-66002/ (Markdown: https://insights.sbomify.com/CVE-2026-66002/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-66002
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-66002
- OSV: https://osv.dev/vulnerability/CVE-2026-66002

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-66002/
Summaries are generated and may contain mistakes; the official description above is the record.