---
id: "CVE-2020-11899"
kind: "vulnerability"
aliases: ["CVE-2020-11899"]
title: "Treck TCP/IP stack IPv6: Treck TCP/IP stack Out-of-Bounds Read Vulnerability"
severity: "medium"
cvss: 5.4
epss: 0.1842
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Treck TCP/IP stack IPv6", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["embedded", "exploited", "infrastructure", "iot", "ipv6", "treck-tcp-ip"]
not_affected_if: ["ipv6-disabled", "no-treck-stack"]
published_at: "2020-06-17T11:15:10+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-11899", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2020-11899", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-11899", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Treck TCP/IP stack IPv6: Treck TCP/IP stack Out-of-Bounds Read Vulnerability

The Treck TCP/IP stack has an IPv6 out-of-bounds read flaw that lets a crafted packet make the device read memory past a buffer. CISA lists it as actively exploited, so attackers can likely leak memory contents or crash the device.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Treck TCP/IP stack IPv6 affected ? fixed ?

## Fix

Apply the vendor's updates per CISA guidance; the sources do not name the fixed version.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-11899
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2020-11899
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2020-11899

## From the sources

The Treck TCP/IP stack contains an IPv6 out-of-bounds read vulnerability.

CISA required action: Apply updates per vendor instructions.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_