CVE-2026-25823

9.8 criticalEPSS 0.8%

Critical (9.8). EPSS 0.8% chance of exploitation in the next 30 days.

HMS Networks Ewon Flexy with firmware before 15.0s4, Cosy+ with firmware 22.xx before 22.1s6, and Cosy+ with firmware 23.xx before 23.0s3 have a stack buffer overflow that leads to a Denial of Service, which can also be exploited to achieve Unauthenticated Remote Code Execution.

Severity

CVSS 3.1

9.8 critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.8% chance of exploitation in the next 30 days; higher than 55% of CVEs (scores of 2026-10-31)
CWE: CWE-121
Published: 2026-03-13
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

References

https://hmsnetworks.blob.core.windows.net/nlw/docs/default-source/products/cybersecurity/security-advisory/hms-security-advisory-2026-03-09-001---ewon-several-flexy-and-cosy--vulnerabilities.pdf?sfvrsn=f7c027b8_13
https://www.hms-networks.com/p/flexy20500-00ma-ewon-flexy-205

Check your stack JSON