CVE-2020-25066: Treck TCP/IP Buffer Overflow Vulnerability

CVE-2020-25066 Overview

CVE-2020-25066 is a heap-based buffer overflow vulnerability in the Treck HTTP Server component affecting versions before 6.0.1.68. This vulnerability allows remote attackers to cause a denial of service (crash/reset) or potentially execute arbitrary code on affected systems. The Treck TCP/IP stack is widely embedded in IoT devices, industrial control systems, and networking equipment, making this vulnerability particularly concerning for critical infrastructure.

Critical Impact

Remote attackers can exploit this heap-based buffer overflow to crash affected devices or potentially achieve arbitrary code execution without authentication, affecting a wide range of embedded systems and IoT devices running the Treck TCP/IP stack.

Affected Products

• Treck TCP/IP stack versions before 6.0.1.68
• Embedded systems and IoT devices utilizing the Treck HTTP Server component
• Industrial control systems and networking equipment with vulnerable Treck implementations

Discovery Timeline

• 2020-12-22 - CVE-2020-25066 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2020-25066

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write), specifically manifesting as a heap-based buffer overflow in the HTTP Server component of the Treck TCP/IP stack. The flaw exists in how the HTTP Server processes incoming requests, where insufficient bounds checking allows attackers to write data beyond the allocated heap buffer boundaries.

The Treck TCP/IP stack is a lightweight, high-performance networking stack commonly embedded in resource-constrained devices such as industrial controllers, medical devices, printers, and IoT sensors. Due to the widespread adoption of this stack across various embedded platforms, the vulnerability has significant reach across multiple industries and device types.

When exploited, the heap corruption can lead to device crashes and resets (denial of service), or in more sophisticated attacks, could potentially allow an attacker to overwrite critical heap metadata or function pointers, enabling arbitrary code execution on the target device.

Root Cause

The root cause of CVE-2020-25066 is improper bounds checking within the Treck HTTP Server's request handling logic. When processing HTTP requests, the server fails to properly validate the length of input data before copying it into a fixed-size heap buffer. This allows an attacker to supply a specially crafted HTTP request with oversized data that exceeds the buffer capacity, resulting in heap memory corruption.

Attack Vector

The attack vector for this vulnerability is network-based, requiring no authentication or user interaction. An attacker can remotely target any device running the vulnerable Treck HTTP Server component that is accessible over the network. The attack can be executed by sending specially crafted HTTP requests designed to trigger the buffer overflow condition.

The exploitation process typically involves:

1. Identifying devices running the vulnerable Treck HTTP Server component on the network
2. Crafting malicious HTTP requests with payloads designed to overflow the heap buffer
3. Sending these requests to trigger the overflow, causing either a denial of service or potential code execution

Due to the nature of heap-based vulnerabilities, successful exploitation for code execution may require additional techniques such as heap spraying or precise heap grooming to achieve reliable control flow hijacking.

Detection Methods for CVE-2020-25066

Indicators of Compromise

• Unexpected crashes or resets of embedded devices running Treck TCP/IP stack
• Abnormal HTTP traffic patterns targeting embedded web servers
• Network traffic containing unusually large HTTP request headers or payloads
• Repeated connection attempts followed by device unavailability

Detection Strategies

• Deploy network intrusion detection systems (IDS) with signatures for oversized HTTP requests targeting embedded devices
• Monitor for anomalous HTTP traffic patterns to known embedded devices on the network
• Implement asset inventory to identify devices running vulnerable Treck TCP/IP stack versions
• Review device logs for repeated crash/reset events that may indicate exploitation attempts

Monitoring Recommendations

• Enable logging on network devices and firewalls for HTTP traffic to embedded systems
• Implement network segmentation to isolate IoT and embedded devices from untrusted networks
• Deploy honeypots mimicking vulnerable embedded devices to detect scanning and exploitation attempts
• Establish baseline behavior for embedded device network communications to identify anomalies

How to Mitigate CVE-2020-25066

Immediate Actions Required

• Identify all devices in your environment running the Treck TCP/IP stack
• Update affected devices to Treck TCP/IP stack version 6.0.1.68 or later
• Implement network segmentation to isolate vulnerable devices from untrusted networks
• Disable or restrict access to HTTP services on embedded devices where not required

Patch Information

Treck has released an updated version of the TCP/IP stack (6.0.1.68) that addresses this vulnerability. Organizations should contact their device manufacturers to obtain firmware updates that incorporate the patched Treck library. For detailed information about available patches and remediation guidance, refer to the Treck Vulnerability Response Information page.

Additionally, NetApp has published a security advisory for affected products: NetApp Security Advisory NTAP-20210201-0003.

Workarounds

• Implement strict network access controls to limit HTTP access to embedded devices
• Deploy web application firewalls (WAF) or intrusion prevention systems (IPS) to filter malicious HTTP requests
• Disable the HTTP Server component on devices where remote web access is not required
• Use VPN or other secure tunneling for remote access to embedded device management interfaces

For devices where patches are not available, network-level mitigations should be implemented to reduce the attack surface. This includes placing vulnerable devices behind firewalls that restrict incoming HTTP connections to trusted sources only, and implementing network monitoring to detect and alert on potential exploitation attempts.