Privilege escalation in Fluxbuilder Mstore API

CVE-2026-27543

Unauthenticated Privilege Escalation in MStore API <= 4.20.0 versions.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (28.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 28.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-27543: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-27543?
CVE-2026-27543 is a high-severity vulnerability in Fluxbuilder Mstore API, classified under Incorrect Privilege Assignment. CVSS score: 8.1/10. Published 2026-08-13.
How severe is CVE-2026-27543?
High severity. CVSS v3 base score is 8.1 out of 10.