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 [email protected] and (if CBC is used) the [email protected] 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

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Debian: Security Advisory (DSA-5586-1)

The remote host is missing an update for the Debian SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

Debian: Security Advisory (DSA-5588-1)

The remote host is missing an update for the Debian SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

[SECURITY] [DSA 5588-1] putty security update

------------------------------------------------------------------------- Debian Security Advisory DSA-5588-1 [email protected] https://www.debian.org/security/ Salvatore Bonaccorso December 24, 2023 https://www.debian.org/security/faq -...

SSH Attack Surface (CVE-2023-48795): Find and Patch With CyberSecurity Asset Management Before the Grinch Arrives

Secure Shell Protocol SSH has been a cornerstone of cryptography and security since it was developed in early 1995. Organizations rely on SSH for secure communications within several popular software products. The recent Terrapin Attack highlights the importance of maintaining full visibility of...

SUSE: Security Advisory (SUSE-SU-2023:4946-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

OpenSSH < 9.6 Multiple Vulnerabilities

The version of OpenSSH installed on the remote host is prior to 9.6. It is, therefore, affected by multiple vulnerabilities as referenced in the release-9.6 advisory. - ssh1, sshd8: implement protocol extensions to thwart the so-called Terrapin attack discovered by Fabian Bumer, Marcus Brinkmann...

Debian DSA-5586-1 : openssh - security update

The remote Debian 11 / 12 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-5586 advisory. Several vulnerabilities have been discovered in OpenSSH, an implementation of the SSH protocol suite. CVE-2021-41617 It was discovered that sshd failed to...

SUSE-SU-2023:4946-1 Security update for libssh2_org

This update for libssh2org fixes the following issues: - CVE-2023-48795: Fixed prefix truncation breaking ssh channel integrity Terrapin Attack bsc1218127...

Fedora 39 : libssh (2023-0733306be9)

The remote Fedora 39 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2023-0733306be9 advisory. New upstream release fixing CVE-2023-48795, CVE-2023-6004, CVE-2023-6918 Tenable has extracted the preceding description block directly from the...

SUSE SLES15 Security Update : openssh (SUSE-SU-2023:4904-1)

The remote SUSE Linux SLES15 / SLESSAP15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2023:4904-1 advisory. - CVE-2023-48795: Fixed prefix truncation breaking ssh channel integrity bsc1217950. Tenable has extracted the preceding description block...

SUSE SLES12 Security Update : libssh2_org (SUSE-SU-2023:4946-1)

The remote SUSE Linux SLES12 / SLESSAP12 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2023:4946-1 advisory. - CVE-2023-48795: Fixed prefix truncation breaking ssh channel integrity Terrapin Attack bsc1218127. Tenable has extracted the preceding...

SUSE SLES12 Security Update : openssh (SUSE-SU-2023:4903-1)

The remote SUSE Linux SLES12 / SLESSAP12 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2023:4903-1 advisory. - CVE-2023-48795: Fixed prefix truncation breaking ssh channel integrity bsc1217950. Tenable has extracted the preceding description block...

Prefix Truncation Attacks in SSH Specification (Terrapin Attack)

The remote SSH server is supporting an specific encryption algorithm or MAC. Parts of their SSH specification are vulnerable to a novel prefix truncation attack a.k.a. Terrapin attack. SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, a...

Slackware Linux 14.0 / 14.1 / 14.2 / 15.0 / current proftpd Vulnerability (SSA:2023-354-01)

The version of proftpd installed on the remote host is prior to 1.3.8b. It is, therefore, affected by a vulnerability as referenced in the SSA:2023-354-01 advisory. - The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attacker...

openSUSE 15 Security Update : putty (openSUSE-SU-2023:0411-1)

The remote openSUSE 15 host has a package installed that is affected by a vulnerability as referenced in the openSUSE- SU-2023:0411-1 advisory. - The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity...

OpenBSD OpenSSH < 9.6 Multiple Vulnerabilities (Terrapin Attack)

OpenBSD OpenSSH is prone to multiple vulnerabilities. SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only CPE = "cpe:/a:openbsd:openssh";...

Ubuntu: Security Advisory (USN-6560-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2023 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

FreeBSD : putty -- add protocol extension against 'Terrapin attack' (91955195-9ebb-11ee-bc14-a703705db3a6)

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the 91955195-9ebb-11ee-bc14-a703705db3a6 advisory. - The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other...

USN-6561-1 libssh vulnerability

Fabian Bäumer, Marcus Brinkmann, Jörg Schwenk discovered that the SSH protocol was vulnerable to a prefix truncation attack. If a remote attacker was able to intercept SSH communications, extension negotiation messages could be truncated, possibly leading to certain algorithms and features being...