CVE-2023-48795 (https://terrapin-attack.com/): 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 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, and PuTTY before 0.80; and there could be effects on Bitvise SSH through 9.31, AsyncSSH through 2.14.1, libssh through 0.10.5, and golang.org/x/crypto through 2023-12-17.
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=9b38a63644a6643c8356ab3720c391f47446dda7 commit 9b38a63644a6643c8356ab3720c391f47446dda7 Author: Sam James <sam@gentoo.org> AuthorDate: 2023-12-20 15:10:20 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2023-12-20 15:18:39 +0000 net-ftp/proftpd: add 1.3.8b Bug: https://bugs.gentoo.org/920385 Signed-off-by: Sam James <sam@gentoo.org> net-ftp/proftpd/Manifest | 1 + net-ftp/proftpd/proftpd-1.3.8b.ebuild | 304 ++++++++++++++++++++++++++++++++++ 2 files changed, 305 insertions(+)
