Vulnerability · Published Apr 21, 2026 · Assigned by GitHub_M
CVE-2026-40586blueprintUE: Login Endpoint Has No Rate Limiting, Lockout, or Brute-Force Protection
High 7.5
In plain English
A high-severity security flaw in blueprintue-self-hosted-edition from blueprintue. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities).
Official description
blueprintUE is a tool to help Unreal Engine developers. Prior to 4.2.0, the login form handler performs no throttling of any kind. Failed authentication attempts are processed at full network speed with no IP-based rate limiting, no per-account attempt counter, no temporary lockout, no progressive delay (Tarpit), and no CAPTCHA challenge. An attacker can submit an unlimited number of credential guesses. The password policy (10+ characters, mixed case, digit, special character) reduces the effective keyspace but does not prevent dictionary attacks, credential stuffing from breached databases, or targeted attacks against known users with predictable passwords. This vulnerability is fixed in 4.2.0.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| blueprintue | blueprintue-self-hosted-edition | < 4.2.0 |
Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N