This post is a quick vulnerability report summary for a vulnerability we found while fuzzing the TCP/IP stack CycloneTCP.

In this blog post we analyze a denial of service vulnerability affecting the IPv6 stack of Windows. This issue, whose root cause can be found in the mishandling of IPv6 fragments, was patched by Microsoft in their February 2021 security bulletin.

This blog post provides details about four vulnerabilities we found in the IPv6 stack of FreeBSD, more specifically in rtsold(8), the router solicitation daemon. The bugs affected all supported versions of FreeBSD, and the most severe of them could allow an attacker attached to the same physical link to gain remote code execution as root on vulnerable systems. The vulnerabilities were discovered and reported to FreeBSD Security Team in November 2020. FreeBSD issued fixes for these bugs on December 1st, 2020 along with security advisory FreeBSD-SA-20:32.rtsold.

This blog post analyzes the vulnerability known as "Bad Neighbor" or CVE-2020-16898, a stack-based buffer overflow in the IPv6 stack of Windows, which can be remotely triggered by means of a malformed Router Advertisement packet.

Broadcom is one of the major vendors of wireless devices worldwide. Since these chips are so widespread they constitute a high value target to attackers and any vulnerability found in them should be considered to pose high risk. In this blog post I provide an account of my internship at Quarkslab which included obtaining, reversing and fuzzing the firmware, and finding a few new vulnerabilities.