What is CVE-2026-45289?

CVE-2026-45289 is a medium-severity vulnerability in Cloudburstmc Protocol, classified under Improper Authentication. CVSS score: 5.3/10. Published 2026-06-02.

How severe is CVE-2026-45289?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Cloudburstmc Protocol

CVE-2026-45289

CloudburstMC Protocol is a protocol library for Minecraft Bedrock Edition. Prior to version 3.0.0.Beta12-20260420.182526-15, CloudburstMC Protocol is partially missing validation for FULL type authentication tokens (Cloudburst/Protocol). T…

Vulnerability class: Broken Authentication

EPSS: 0.000 (5.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Cloudburstmc Protocol — versions < 3.0.0.Beta12-20260420.182526-15

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

security-advisories@github.com (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-45289?: CVE-2026-45289 is a medium-severity vulnerability in Cloudburstmc Protocol, classified under Improper Authentication. CVSS score: 5.3/10. Published 2026-06-02.
How severe is CVE-2026-45289?: Medium severity. CVSS v3 base score is 5.3 out of 10.