CVE-2025-26409: Access to Bootloader and Shell Over Serial Interface

Severity: medium (CVSS 6.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-02-11 · updated 2026-06-17
Weakness: CWE-1191

Description

A serial interface can be accessed with physical access to the PCB of Wattsense Bridge devices. After connecting to the interface, access to the bootloader is possible, as well as a Linux login prompt. The bootloader access can be used to gain a root shell on the device. This issue is fixed in recent firmware versions BSP >= 6.4.1.

Affected products

Wattsense Bridge: before 6.4.1 — fixed in 6.4.1

How to fix

Upgrade to a fixed version: Wattsense Bridge 6.4.1. Check the vendor advisory for mitigations.

References

https://r.sec-consult.com/wattsense
https://support.wattsense.com/hc/en-150/articles/13366066529437-Release-Notes
http://seclists.org/fulldisclosure/2025/Feb/9

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