Severity
6.5MEDIUMNVD
EPSS
0.1%
top 69.42%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedAug 31
Latest updateMay 24

Description

A flaw has been found in libssh in versions prior to 0.9.6. The SSH protocol keeps track of two shared secrets during the lifetime of the session. One of them is called secret_hash and the other session_id. Initially, both of them are the same, but after key re-exchange, previous session_id is kept and used as an input to new secret_hash. Historically, both of these buffers had shared length variable, which worked as long as these buffers were same. But the key re-exchange operation can also cha

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitability: 2.8 | Impact: 3.6

Affected Packages5 packages

NVDlibssh/libssh0.9.10.9.6
Debianlibssh/libssh< 0.9.5-1+deb11u1+3
CVEListV5libssh/libsshlibssh 0.9.6

Also affects: Debian Linux 10.0, 11.0, Fedora 33, 34, 35, Enterprise Linux 8.0

Patches

🔴Vulnerability Details

3
GHSA
GHSA-4wwm-f449-qwpq: A flaw has been found in libssh in versions prior to 02022-05-24
OSV
CVE-2021-3634: A flaw has been found in libssh in versions prior to 02021-08-31
CVEList
CVE-2021-3634: A flaw has been found in libssh in versions prior to 02021-08-31

📋Vendor Advisories

5
Oracle
Oracle Oracle MySQL Risk Matrix: Workbench: libssh — CVE-2021-36342022-01-15
Red Hat
libssh: possible heap-based buffer overflow when rekeying2021-08-26
Ubuntu
libssh vulnerability2021-08-26
Microsoft
A flaw has been found in libssh in versions prior to 0.9.6. The SSH protocol keeps track of two shared secrets during the lifetime of the session. One of them is called secret_hash and the other sessi2021-08-10
Debian
CVE-2021-3634: libssh - A flaw has been found in libssh in versions prior to 0.9.6. The SSH protocol kee...2021
CVE-2021-3634 — Out-of-bounds Write in Libssh | cvebase