A Meshtastic sniffer for DragonOS has been introduced. Meshtastic has gained popularity in recent years because it does not require a license and its hardware is very cheap compared to amateur radio equipment. The number of channels and modes is large. If the user does not have prior knowledge, the sheer number of channels and modes makes it difficult to find where conversations are taking place. To solve this problem, [cemaxecuter] added a Meshtastic sniffer to DragonOS, a radio-focused Linux distribution.
Written in C, the software comes as a standalone binary and does not require GNU Radio. Scanning takes place while DragonOS is running. While DragonOS is running, the software scans the entire Meshtastic band simultaneously, detects traffic, and can decrypt that traffic if the key is known. The project uses a HackRF as the software-defined radio; although the device does not cover all Meshtastic frequencies, it picks up most of them. The developer, who powered up his own node, reports that the software quickly detected it and displayed its details in the terminal. The software makes it easier to find conversations. Detecting other networks through wardriving also becomes easier.
Why it matters
This development shakes the privacy assumptions of the Meshtastic community, which is made up of people seeking license-free and inexpensive communication. While the sheer number of channels and modes has until now provided a de facto layer of privacy, the ability to scan the entire band simultaneously with a single device largely removes that protection; the fact that the HackRF does not cover all frequencies, however, leaves a limited blind spot. Although message content cannot be read without the key, the ability to detect the presence of traffic and node details requires users to rethink what information they are exposing. The tool, which also makes it easier to map nearby networks through wardriving, concerns not only amateur radio enthusiasts and security researchers but also communities that use Meshtastic for license-free and inexpensive communication. The open question is how users will manage their encryption keys and channel choices in the face of this new visibility.