CVE-2025-55293: Meshtastic Firmware

Critical severity, CVSS 9.8. EPSS: 0.4% chance of exploitation in the next 30 days.

Meshtastic is an open source mesh networking solution. Prior to v2.6.3, an attacker can send NodeInfo with a empty publicKey first, then overwrite it with a new key. First sending a empty key bypasses 'if (p.public_key.size > 0) {', clearing the existing publicKey (and resetting the size to 0) for a known node. Then a new key bypasses 'if (info->user.public_key.size > 0) {', and this malicious key is stored in NodeDB. This vulnerability is fixed in 2.6.3.

Affected products

• Meshtastic Meshtastic Firmware: before 2.6.3 (fixed in 2.6.3)

Published 2025-08-18. Last modified 2026-06-17.