Intel network card driver was exposed to destroy IPv6 connections, affecting OneNote, OneDrive and Microsoft 365

IT House News on October 8. According to a report by German technology blog BornCity today, a user discovered that the Intel network card driver installed through Windows Update has a bug that will silently destroy IPv6 network connections, causing services such as Microsoft OneNote, Microsoft 365, OneDrive, Teams and Azure portal to be unable to function properly. According to the user's description, OneNote on his Samsung Galaxy Book laptop continued to display empty notes for about three weeks, while also prompting that it was "already up to date." So he submitted the problem to Microsoft support in August this year and escalated it, but five weeks later the cause was still not found. Ultimately, the user completed packet-level forensic analysis over an entire night using Claude. Claude captured the network traffic of the Windows system, measured the time point of connection reset, checked and disabled the network filtering driver one by one, and finally located the Intel Connectivity Performance Suite (ICPS). According to CircleID, the problem stems from the fact that the flow control driver of ICPS resets the IPv6 Flow Label field of each TCP packet to 0 after the handshake when processing IPv6 packets. According to the RFC 6437 specification, the Flow Label should remain consistent for the lifetime of the connection. Microsoft's cloud edge load balancing system uses this field to decide which backend server the packet should be sent to. After the tag is cleared, subsequent packets are routed to another server that has never participated in the connection, which then returns a reset signal. According to the technical analysis report on the Intel official community, the driver component involved in the defect is IntcCo11X64.sys 11.5.11.19, which belongs to Rivet Networks (has been