The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against SSH's use of ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in chacha20-poly1305@openssh.com and (if CBC is used) the -etm@openssh.com MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80, AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0, Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15, SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH through 18.2.0, ProFTPD before 1.3.8b (and before 1.3.9rc2), ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144, CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, Apache MINA sshd through 2.11.0, sshj through 0.37.0, TinySSH through 20230101, trilead-ssh2 6401, LANCOM LCOS and LANconfig, FileZilla before 3.66.4, Nova before 11.8, PKIX-SSH before 14.4, SecureCRT before 9.4.3, Transmit5 before 5.10.4, Win32-OpenSSH before 9.5.0.0p1-Beta, WinSCP before 6.2.2, Bitvise SSH Server before 9.32, Bitvise SSH Client before 9.33, KiTTY through 0.76.1.13, the net-ssh gem 7.2.0 for Ruby, the mscdex ssh2 module before 1.15.0 for Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N9bis Kitty
APP9Bis≤ 0.76.1.13Apache Sshd
APPApache≤ 2.11.0Apache Sshj
APPApache≤ 0.37.0Apple macOS
OSApple14.0 – 14.4 (bez)Asyncssh Project Asyncssh
APPAsyncssh Project< 2.14.2Bitvise Ssh Client
APPBitvise< 9.33Bitvise Ssh Server
APPBitvise< 9.32Connectbot Sshlib
APPConnectbot< 2.2.22Crates Thrussh
APPCrates< 0.35.1Crushftp
APPCrushftp< 10.6.0≤ 10.6.0Debian
OSDebian10.0Dropbear Ssh Project Dropbear Ssh
APPDropbear Ssh Project< 2022.83Erlang Erlang\/otp
APPErlang< 22.3.4.2726.0 – 26.2.1 (bez)25.0 – 25.3.2.8 (bez)24.0 – 24.3.4.15 (bez)23.0 – 23.3.4.20 (bez)Fedora Project Fedora
OSFedoraproject3839Filezilla Project Filezilla Client
APPFilezilla-Project< 3.66.4Freebsd
OSFreebsd≤ 12.4Gentoo Security
APPGentoowszystkie wersjeGolang Crypto
APPGolang< 0.17.0Jadaptive Maverick Synergy Java Ssh Api
APPJadaptive< 3.1.0-snapshotLancom Systems Lanconfig
OSLancom-Systemswszystkie wersjeLancom Systems Lcos
OSLancom-Systems≤ 3.66.4Lancom Systems Lcos Fx
OSLancom-Systemswszystkie wersjeLancom Systems Lcos Lx
OSLancom-Systemswszystkie wersjeLancom Systems Lcos Sx
OSLancom-Systems4.205.20Libssh
APPLibssh< 0.10.6Libssh2
APPLibssh2< 1.11.1Matez Jsch
APPMatez< 0.2.15Netgate Pfsense Ce
APPNetgate≤ 2.7.2Netgate Pfsense Plus
APPNetgate≤ 23.09.1Netsarang Xshell 7
APPNetsarang< build__0144
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