fastd is a VPN daemon which tunnels IP packets and Ethernet frames over UDP. When receiving a data packet from an unknown IP address/port combination, fastd will assume that one of its connected peers has moved to a new address and initiate a reconnect by sending a handshake packet. This "fast reconnect" avoids having to wait for a session timeout (up to ~90s) until a new connection is established. Even a 1-byte UDP packet just containing the fastd packet type header can trigger a much larger handshake packet (~150 bytes of UDP payload). Including IPv4 and UDP headers, the resulting amplification factor is roughly 12-13. By sending data packets with a spoofed source address to fastd instances reachable on the internet, this amplification of UDP traffic might be used to facilitate a Distributed Denial of Service attack. This vulnerability is fixed in v23.

The FastDup WordPress plugin before 2.2 does not prevent directory listing in sensitive directories containing export files.

Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Ninja Team FastDup – Fastest WordPress Migration & Duplicator.This issue affects FastDup – Fastest WordPress Migration & Duplicator: from n/a through 2.1.7.

A vulnerability, which was classified as critical, has been found in sjqzhang go-fastdfs up to 1.4.3. Affected by this issue is the function upload of the file /group1/uploa of the component File Upload Handler. The manipulation leads to path traversal: '../filedir'. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-224768.

receive.c in fastd before v21 allows denial of service (assertion failure) when receiving packets with an invalid type code.