CVE-2026-109439

Lantronix XPress-DR and XPress-DR-I (CoBos-family) firmware through 8.1.0.0 contains a missing authentication vulnerability that allows remote attackers to read and persistently overwrite device configuration by sending crafted frames to the unauthenticated UDP configuration protocol on port 30718. Attackers can send a type 0xF8 query to read live configuration data and a type 0xFD frame with exactly 0x78 body bytes to rewrite the device IP address and serial-channel forwarding records, causing changes to commit to EEPROM and persist across reboots. The XPress-DR product series reached end-of-life/end-of-support in February 2025.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://cdn.lantronix.com/wp-content/uploads/pdf/PCN-753-Rev-B-EOL-Notice-XPRESS.pdf?xnotes__c=I%20am%20interested%20in%20the%20XPress%20DR%20/%20XPress%20DR-IAP.
https://www.vulncheck.com/advisories/lantronix-xpress-dr-unauthenticated-configuration-write-via-udp-30718

Configurations

No configuration.

History

14 Oct 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 17:18

Updated : 2026-10-16 19:00

NVD link : CVE-2026-109439

Mitre link : CVE-2026-109439

CVE.ORG link : CVE-2026-109439

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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