USN-7051-1: AsyncSSH vulnerability
2 October 2024
A protocol flaw was fixed in AsyncSSH.
Releases
Packages
- python-asyncssh - asyncio-based client and server implementation of SSHv2 protocol
Details
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 downgraded. This issue is known as the Terrapin attack. This update
adds protocol extensions to mitigate this issue.
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 24.04
Ubuntu 22.04
-
python3-asyncssh
-
2.5.0-1ubuntu0.1~esm1
Available with Ubuntu Pro
Ubuntu 20.04
In general, a standard system update will make all the necessary changes.
References
Related notices
- USN-6560-1: openssh-client, openssh, openssh-server, openssh-sftp-server, openssh-tests, ssh, ssh-askpass-gnome
- USN-6561-1: libssh-gcrypt-4, libssh-doc, libssh-gcrypt-dev, libssh, libssh-dev, libssh-4
- USN-6560-2: openssh-client, openssh, ssh-krb5, openssh-server, openssh-client-ssh1, openssh-sftp-server, ssh, ssh-askpass-gnome
- USN-6585-1: libssh2, libssh2-1, libssh2-1-dev
- USN-6589-1: filezilla, filezilla-common
- USN-6598-1: paramiko, python3-paramiko, paramiko-doc
- USN-6738-1: lxd, lxd-tools, lxd-client, golang-github-lxc-lxd-dev, lxc2