Is CVE-2026-109439 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-109439?

CVE-2026-109439 has a CVSS v3 severity of CRITICAL (9.8).

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CVE-2026-109439

Description

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.