USN-6560-1
Advisory lineage Upstream: 4 Downstream: 0
Published: 19 Dec 2023, 13:02
Last modified:27 Apr 2026, 17:17
Vulnerability Summary
Overall Risk (default)
minimal
0/100 CVSS Score
No data
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected
Timeline
19 Dec 2023, 13:02
Published
Vulnerability first disclosed
27 Apr 2026, 17:17
Last Modified
Vulnerability information updated
Description
openssh vulnerabilities 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) Luci Stanescu discovered that OpenSSH incorrectly added destination constraints when smartcard keys were added to ssh-agent, contrary to expectations. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 23.04. (CVE-2023-28531)
Affected Systems
- ubuntu•openssh
< 1:8.2p1-4ubuntu0.10 | < 1:8.9p1-3ubuntu0.5