CVE-2026-27850: Improper verification in Linksys MR9600, Linksys MX4200

Published Feb 25, 2026
·
Updated

Due to an improperly configured firewall rule, the router will accept any connection on the WAN port with the source port 5222, exposing all services which are normally only accessible through the local network. This issue affects MR9600: 1.0.4.205530; MX4200: 1.0.13.210200.

Affected Software

2 affected components
LinkSys MR9600
LinkSys MX4200

Event History

Feb 25, 2026
CVE Published
via MITRE·04:58 PM
Data Sourced
via MITRE·04:58 PM
DescriptionWeakness
Data Sourced
via NVD·06:23 PM
DescriptionSeverity
Oct 1, 58139
Event
via FIRST·10:33 AM
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Frequently Asked Questions

1

What devices are affected by CVE-2026-27850?

CVE-2026-27850 affects Linksys MR9600 and Linksys MX4200 routers.

2

What is the severity of CVE-2026-27850?

CVE-2026-27850 is considered a critical vulnerability due to improper firewall configurations.

3

How do I fix CVE-2026-27850?

To fix CVE-2026-27850, review and update your firewall settings to block unwanted access on the WAN port.

4

What are the risks associated with CVE-2026-27850?

CVE-2026-27850 may expose sensitive services normally restricted to the local network, increasing the risk of unauthorized access.

5

How does CVE-2026-27850 impact router security?

CVE-2026-27850 compromises router security by allowing connections on the WAN port, potentially leading to data breaches.

Contact

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