Subject: [ASA-201810-10] libssh: authentication bypass Arch Linux Security Advisory ASA-201810-10 ========================================== Severity: Critical Date : 2018-10-17 CVE-ID : CVE-2018-10933 Package : libssh Type : authentication bypass Remote : Yes Link : https://security.archlinux.org/AVG-780 Summary ======= The package libssh before version 0.8.4-1 is vulnerable to authentication bypass. Resolution ========== Upgrade to 0.8.4-1. # pacman -Syu "libssh>=0.8.4-1" The problem has been fixed upstream in version 0.8.4. Workaround ========== None. Description =========== An authentication bypass vulnerability has been discovered in libssh versions prior to 0.7.6 and 0.8.4, in the server-side state machine. By presenting the server an SSH2_MSG_USERAUTH_SUCCESS message in place of the SSH2_MSG_USERAUTH_REQUEST message which the server would expect to initiate authentication, the attacker could successfully authenticate without any credentials, resulting in unauthorized access. Impact ====== A remote attacker is able to successfully authenticate without any credentials, resulting in unauthorized access. References ========== https://www.libssh.org/2018/10/16/libssh-0-8-4-and-0-7-6-security-and-bugfix-release/ https://www.libssh.org/security/advisories/CVE-2018-10933.txt https://git.libssh.org/projects/libssh.git/commit/?id=2bddafeb709eacc80ad31fec40479f9b628a8bd7 https://git.libssh.org/projects/libssh.git/commit/?id=825f4ba96407abe8cebb046a7503fa2bf5de9df6 https://git.libssh.org/projects/libssh.git/commit/?id=20981bf2296202e95d7919394d4610ae3a876cfa https://git.libssh.org/projects/libssh.git/commit/?id=5d7414467d6dac100a93df761b06de5cd07fc69a https://git.libssh.org/projects/libssh.git/commit/?id=459868c4a57d2d11cf7835655a8d1a5cf034ccb4 https://git.libssh.org/projects/libssh.git/commit/?id=68b0c7a93448123cc0d6a04d3df40d92a3fd0a67 https://git.libssh.org/projects/libssh.git/commit/?id=75be012b4a14f4550ce6ad3f126e559f44dbde76 https://git.libssh.org/projects/libssh.git/commit/?id=e1548a71bdac73da084174ab1d6d2713edd93f6e https://security.archlinux.org/CVE-2018-10933