A denial of service vulnerability exists in the ICMP and ICMPv6 parsing functionality of Weston Embedded uC-TCP-IP v3.06.01. A specially crafted network packet can lead to an out-of-bounds read. An attacker can send a malicious packet to trigger this vulnerability.This vulnerability concerns a denial of service within the parsing an IPv4 ICMP packet.
In Silicon Labs uC/TCP-IP 3.6.0, TCP ISNs are improperly random.
In Oryx CycloneTCP 1.9.6, TCP ISNs are improperly random.
In Microchip MPLAB Net 3.6.1, TCP ISNs are improperly random.
In Contiki 4.5, TCP ISNs are improperly random.
In FNET 4.6.3, TCP ISNs are improperly random.
In PicoTCP 1.7.0, TCP ISNs are improperly random.
In SIMATIC MV400 family versions prior to v7.0.6, the ISN generator is initialized with a constant value and has constant increments. An attacker could predict and hijack TCP sessions.
An issue was discovered in Ethernut Nut/OS 5.1. The code that generates Initial Sequence Numbers (ISNs) for TCP connections derives the ISN from an insufficiently random source. As a result, an attacker may be able to determine the ISN of current and future TCP connections and either hijack existing ones or spoof future ones. While the ISN generator seems to adhere to RFC 793 (where a global 32-bit counter is incremented roughly every 4 microseconds), proper ISN generation should aim to follow at least the specifications outlined in RFC 6528.