CVE-2025-55292 Overview
CVE-2025-55292 is a high-severity authentication bypass vulnerability affecting the Meshtastic open source mesh networking solution. The vulnerability stems from a fundamental architectural flaw where nodes are identified by their NodeID (derived from MAC address) rather than their public key, enabling attackers to forge NodeInfo messages and compromise the security of the mesh network.
Critical Impact
Attackers can forge NodeInfo on behalf of victim nodes, enabling message interception and persistent node impersonation across the mesh network.
Affected Products
- Meshtastic firmware versions prior to 2.7.6.834c3c5
- All Meshtastic mesh network deployments using NodeID-based authentication
- Meshtastic devices operating in or susceptible to HAM mode configuration
Discovery Timeline
- 2026-01-28 - CVE CVE-2025-55292 published to NVD
- 2026-01-29 - Last updated in NVD database
Technical Details for CVE-2025-55292
Vulnerability Analysis
The vulnerability exploits a weakness in Meshtastic's node identification architecture. In the current implementation, nodes are identified by their NodeID, which is generated from the device's MAC address rather than cryptographic public keys. This design choice significantly downgrades the security posture of the mesh network.
The attack specifically abuses the HAM (amateur radio) mode, which by design does not use encryption to comply with amateur radio regulations. An attacker can exploit this by forging a NodeInfo message on behalf of a victim node, falsely advertising that the victim has HAM mode enabled. When other nodes in the mesh receive this forged information, they overwrite their NodeDB with the malicious data.
Once the NodeDB is corrupted, nodes attempting to send direct messages to the victim will use the shared channel key instead of Public Key Cryptography (PKC), effectively bypassing the end-to-end encryption that would normally protect these communications. This allows the attacker to potentially intercept or manipulate messages intended for the victim.
Root Cause
The root cause is classified under CWE-348 (Use of Less Trusted Source). The fundamental issue lies in trusting NodeID (MAC-derived) as the authoritative identifier for nodes instead of cryptographic public keys. This trust model allows any network participant to claim identity of another node without cryptographic proof of ownership, as long as they can construct valid-looking NodeInfo messages.
Attack Vector
The attack is network-based and can be executed without authentication or user interaction. An attacker with access to the mesh network can:
- Observe the victim's NodeID on the network
- Craft a forged NodeInfo packet claiming the victim has HAM mode enabled
- Broadcast this forged NodeInfo to other nodes on the mesh
- Wait for nodes to update their NodeDB with the malicious information
- Maintain persistence by resending the forged NodeInfo periodically, especially immediately after the victim broadcasts their legitimate NodeInfo
The vulnerability enables both confidentiality compromise through message interception and integrity violations through node detail manipulation (full name, short code, etc.).
Detection Methods for CVE-2025-55292
Indicators of Compromise
- Unexpected changes in node configuration appearing in NodeDB without legitimate administrative action
- Nodes suddenly appearing with HAM mode enabled when they should be using PKC
- Inconsistencies between a node's advertised capabilities and its historical configuration
- Rapid or repeated NodeInfo updates for the same NodeID from different sources
Detection Strategies
- Monitor for NodeInfo messages that change a node's encryption mode from PKC to HAM mode unexpectedly
- Implement logging of all NodeDB changes to track unauthorized modifications
- Compare incoming NodeInfo data against known baseline configurations for critical nodes
- Deploy network analysis to detect NodeInfo messages originating from unexpected sources
Monitoring Recommendations
- Enable verbose logging on mesh network gateways to capture all NodeInfo exchanges
- Establish baseline node configurations and alert on deviations
- Monitor for patterns indicating NodeInfo race conditions (rapid consecutive updates)
- Consider implementing out-of-band verification for critical node configuration changes
How to Mitigate CVE-2025-55292
Immediate Actions Required
- Upgrade all Meshtastic firmware to version 2.7.6.834c3c5 or later immediately
- Review NodeDB on all mesh nodes for unexpected HAM mode configurations
- Verify the integrity of critical node configurations across the network
- Consider temporarily isolating untrusted nodes until patches are deployed
Patch Information
A patch is available in Meshtastic firmware version 2.7.6.834c3c5. The fix addresses the NodeInfo forgery vulnerability by implementing additional validation. For technical details, refer to the firmware commit e5e8683cdba133e726033101586c3235a8678893 and the GitHub Security Advisory GHSA-45vg-3f35-7ch2.
Workarounds
- Avoid using HAM mode unless required for regulatory compliance
- Implement network segmentation to limit the blast radius of potential attacks
- Manually verify and restore NodeDB configurations if tampering is suspected
- Consider out-of-band verification mechanisms for critical node identity changes
# Firmware update verification
# After updating, verify the firmware version includes the security patch
meshtastic --info | grep -i version
# Expected output should show version 2.7.6.834c3c5 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
