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CVE-2026-109439

CVE-2026-109439 · Lantronix XPress-DR 8.1.0.0 Unauthenticated Configuration Write via UDP 30718

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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 9.3 · Critical · EPSS 0.6%

Published
Updated

Affected products and versions

  • xpress-dr

    Versions
    • ≥ 0, ≤ 8.1.0.0: Affected (custom)

    No fix published

  • xpress-dr-i

    Versions
    • ≥ 0, ≤ 8.1.0.0: Affected (custom)

    No fix published

Original sources

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