github nmap/npcap v0.9990
Npcap 0.9990

Installer, SDK, and debug symbols available from

  • Improve compatibility with WinPcap's behavior regarding injected traffic.
    WinPcap uses inefficient loopback to capture all outbound traffic, but allows
    PacketSetLoopbackBehavior() to avoid this for injected traffic. Because of
    Npcap's more efficient design, injected traffic was never looped back up to
    protocol drivers, causing problems for some users who relied on this behavior.
    Now, injected traffic follows the same path as with WinPcap, though ordinary
    traffic is unaffected. For highest efficiency without loopback, use
    PacketSetLoopbackBehavior(PACKET_DISABLE_LOOPBACK). Fixes #1343,
    #1929, and GNS3/gns3-gui#2936

  • No longer honor NDIS_PACKET_TYPE_ALL_LOCAL set via PacketSetHwFilter().
    This packet filter causes all local traffic to be routed through an unoptimized
    loopback path within NDIS, which was necessary to capture outgoing traffic in
    WinPcap but is no longer needed in Npcap. Instead, this value will be treated as

  • Fix a bug that caused TIMESTAMPMODE_QUERYSYSTEMTIME_PRECISE to fall back to
    TIMESTAMPMODE_QUERYSYSTEMTIME even when KeQuerySystemTimePrecise() was
    available. Fix by Mauro Levra in PR#23.

  • Installer will now install an intermediate CA cert that was missing from some
    systems, which is needed to verify the driver's digital signature. Only
    affects Windows versions prior to Windows 10.

  • Backport a fix from libpcap needed to properly support
    NdisMediumWirelessWan. See #1573.

  • Include experimental support for AirPcap cards if airpcap.dll (not
    included) is installed.

latest releases: v1.55, v1.50, v1.40...
17 months ago