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=d1307b9e32ea830c31939a8083de2b052e6fa3bc commit d1307b9e32ea830c31939a8083de2b052e6fa3bc Author: Sam James <sam@gentoo.org> AuthorDate: 2023-12-19 05:40:50 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2023-12-19 05:40:50 +0000 net-misc/openssh: add 9.6_p1 Bug: https://bugs.gentoo.org/920292 Signed-off-by: Sam James <sam@gentoo.org> net-misc/openssh/Manifest | 2 + net-misc/openssh/openssh-9.6_p1.ebuild | 378 +++++++++++++++++++++++++++++++++ 2 files changed, 380 insertions(+)
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=0b22d07f89b16ac3400e45077702ac4c4492e5a4 commit 0b22d07f89b16ac3400e45077702ac4c4492e5a4 Author: Sam James <sam@gentoo.org> AuthorDate: 2023-12-20 07:12:26 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2023-12-20 07:14:16 +0000 net-misc/openssh: disable problematic -fzero-call-used-regs=* --with-hardening adds the following in addition to flags we already set in our toolchain: * -ftrapv (which is broken with GCC anyway), * -ftrivial-auto-var-init=zero (which is nice, but not the end of the world to not have) * -fzero-call-used-regs=used (history of miscompilations with Clang (bug #872548), ICEs on m68k (bug #920350, gcc PR113086, gcc PR104820, gcc PR104817, gcc PR110934)). Furthermore, OSSH_CHECK_CFLAG_COMPILE does not use AC_CACHE_CHECK, so we cannot just disable -fzero-call-used-regs=used. Therefore, just pass --without-hardening, given it doesn't negate our already hardened toolchain defaults, and avoids adding flags which are known-broken in both Clang and GCC and haven't been proven reliable. Bug: https://bugs.gentoo.org/872548 Bug: https://bugs.gentoo.org/920350 Bug: https://bugs.gentoo.org/920292 Bug: https://gcc.gnu.org/PR113086 Bug: https://gcc.gnu.org/PR104820 Bug: https://gcc.gnu.org/PR104817 Bug: https://gcc.gnu.org/PR110934 Signed-off-by: Sam James <sam@gentoo.org> net-misc/openssh/openssh-9.6_p1-r1.ebuild | 396 ++++++++++++++++++++++++++++++ 1 file changed, 396 insertions(+)
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/data/glsa.git/commit/?id=3dfe782899716a3480c9481c69bca8c231c663a7 commit 3dfe782899716a3480c9481c69bca8c231c663a7 Author: GLSAMaker <glsamaker@gentoo.org> AuthorDate: 2023-12-28 02:21:28 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2023-12-28 02:22:09 +0000 [ GLSA 202312-17 ] OpenSSH: Multiple Vulnerabilities Bug: https://bugs.gentoo.org/920292 Bug: https://bugs.gentoo.org/920722 Signed-off-by: GLSAMaker <glsamaker@gentoo.org> Signed-off-by: Sam James <sam@gentoo.org> glsa-202312-17.xml | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+)
