-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 - ------------------------------------------------------------------------- Debian LTS Advisory DLA-3794-1 [email protected] https://www.debian.org/lts/security/ Bastien Roucariès April 25, 2024 https://wiki.debian.org/LTS - -------------------------------------------------------------------------
Package : putty Version : 0.74-1+deb11u1~deb10u1 CVE ID : CVE-2019-17069 CVE-2020-14002 CVE-2021-36367 CVE-2023-48795 Debian Bug : 990901 Putty, a Telnet/SSH client for X, was vulnerable. CVE-2019-17069 PuTTY allowed remote SSH-1 servers to cause a denial of service by accessing freed memory locations via an SSH1_MSG_DISCONNECT message. CVE-2020-14002 PuTTY had an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allowed man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client). CVE-2021-36367 PuTTY proceeded with establishing an SSH session even if it has never sent a substantive authentication response. This made it easier for an attacker-controlled SSH server to present a later spoofed authentication prompt (that the attacker can use to capture credential data, and use that data for purposes that are undesired by the client user). CVE-2023-48795 PuTTY was vulnerable to Terrapin attack. The SSH transport protocol with certain OpenSSH extensions, allowed 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. 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 and (if CBC is used) the -etm MAC algorithms. For Debian 10 buster, this problem has been fixed in version 0.74-1+deb11u1~deb10u1. We recommend that you upgrade your putty packages. For the detailed security status of putty please refer to its security tracker page at: https://security-tracker.debian.org/tracker/putty Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEXQGHuUCiRbrXsPVqADoaLapBCF8FAmYqwXAACgkQADoaLapB CF9mqw/9GvOHAYhSbEe91OiJALdOISIdYKqFF4I/j/XItQ9iQpJC1g8n2MwXLuJy Wm0pW0gChhh4o9cfSos2v4HPqRiHNW9nzuxVH9vO0YVd2cIFrfkZoIWJ6FQ9ueW3 cshrF0OIrogi+zz6J9xNYKhpTYhP+Uztw0V1YQrJF4ZqbfycByViYMrfj9MhtnTv /QvzaAAZb5pSrxmHmxQrt3ZBaEvFJ9S+UDV0GybPqh/e8g1ZwmWNkFFBspeGDm5+ izZwv0+5nfqVqMGXcpT8KddKQwJ3E6qyfAawAuIu/umZGWY4DBYrUG3jS4s668ut IwgJ0bdMwqO5VWRpdnwOnuqsyX+hZ+dcI0MLaa3Z2CexTcfBuyNbEASUlXgBUK37 UrJmM68jvDasy9zZ5znBPTYQnvTxtmcp04LXuPnon5Tb2wR/qUwpNi4yXJ1H487A aDcxLSd+Sk3mmvkYusArivsQbNNuQmypkhzA7/QQJMy7El35SYksyGzuhcxRyshi BuRRKbRlsEClz9e1nKWFjXW0XAJhwdJMfEcPu1y1G/CJ5DLoCdpppai/QLTjRO6G M2ljRRhY/YAfZgkg09fIbWqqP+7AYRiiXey1fLty9LI9jZuDRF4o1dNHUSYwN1wo MBrjIY2juc/7EMd38fOmzrY5sB8XOifxYEn/J0vZki/O1q/Hop0= =5iDg -----END PGP SIGNATURE-----
