Summary
USN-6560-1 fixed several vulnerabilities in OpenSSH. This update provides
the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.
Original advisory 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. (CVE-2023-48795)
It was discovered that OpenSSH incorrectly handled user names or host names
with shell metacharacters. An attacker could possibly use this issue to
perform OS command injection. This only affected Ubuntu 18.04 LTS. (CVE-2023-51385)
Fixed packages 2
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · Pro 16.04 LTS Pro:16.04:LTS | openssh | 1:7.2p2-4ubuntu2.10+esm5 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | openssh | 1:7.6p1-4ubuntu0.7+esm3 |
Vulnerabilities 2
-
Medium 6.5
In ssh in OpenSSH before 9.6, OS command injection might occur if a user name or host name has shell metacharacters, an…
-
Medium 5.9
Prefix Truncation Attack against ChaCha20-Poly1305 and Encrypt-then-MAC aka Terrapin
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…