CVE-2026-25818
Received Received - Intake
Weak Entropy in HMS Networks Ewon Flexy Authentication Cookies

Publication date: 2026-03-13

Last updated on: 2026-03-13

Assigner: MITRE

Description
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 weak entropy for authentication cookies, allowing an attacker with a stolen session cookie to find the user password by brute-forcing an encryption parameter.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-03-13
Last Modified
2026-03-13
Generated
2026-06-16
AI Q&A
2026-03-13
EPSS Evaluated
2026-06-15
NVD
CVE-2026-25818
EUVD
EUVD-2026-11711
Affected Vendors & Products
Showing 5 associated CPEs
Vendor Product Version / Range
hms_networks cosy_plus to 22.1s6 (exc)
hms_networks cosy_plus to 23.0s3 (exc)
hms_networks ewon_flexy to 15.0s4 (exc)
hms_networks cosy to 22.1s6 (exc)
hms_networks cosy to 23.0s3 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-315 The product stores sensitive information in cleartext in a cookie.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability affects HMS Networks Ewon Flexy and Cosy+ devices with certain firmware versions. The issue is that these devices use weak entropy for authentication cookies. Because of this weakness, an attacker who has stolen a session cookie can brute-force an encryption parameter to discover the user's password.

Impact Analysis

The vulnerability can have a severe impact because it allows an attacker to obtain the user password by brute-forcing an encryption parameter after stealing a session cookie. This can lead to unauthorized access with high confidentiality and integrity impact, as indicated by the CVSS score of 9.1.

Compliance Impact

I don't know

Detection Guidance

I don't know

Mitigation Strategies

I don't know

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-25818. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart