What is the CVSS score of CVE-2026-25818?

CVE-2026-25818 has a CVSS 3.1 base score of 9.1 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. EPSS exploitation probability: 0.0%.

How to fix or mitigate CVE-2026-25818?

Within 24 hours: Inventory all HMS Networks Ewon routers in your environment and identify affected firmware versions (Flexy <15.0s4, Cosy+ 22.xx <22.1s6, Cosy+ 23.xx <23.0s3). Within 7 days: Implement network segmentation to isolate affected routers from untrusted networks, disable remote management features if not operationally critical, and monitor session logs for suspicious authentication attempts. Within 30 days: Contact HMS Networks for patch availability confirmation, establish an upgrade schedule, and conduct security testing post-patch deployment.

CVE-2026-25818

EUVD-2026-11711 CRITICAL

Cleartext Storage of Sensitive Information in a Cookie (CWE-315)

2026-03-13 cve@mitre.org

Information Disclosure

9.1

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.1 CRITICAL

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Lifecycle Timeline

Re-analysis Queued

Apr 27, 2026 - 19:22 vuln.today

cvss_changed

EUVD ID Assigned

Mar 13, 2026 - 20:00 euvd

EUVD-2026-11711

Analysis Generated

Mar 13, 2026 - 20:00 vuln.today

CVE Published

Mar 13, 2026 - 19:54 nvd

CRITICAL 9.1

DescriptionCVE.org

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.