OpenSSH < 8.0 Multiple Vulnerbilities
medium Nessus Network Monitor Plugin ID 701156
Synopsis
The remote SSH server may be affected by multiple vulnerabilities.Description
The installed version of OpenSSH is prior to 8.0 and is affected by multiple vulnerabilities:- The scp client allows remote SSH servers to bypass intended access restrictions via the filename of '.'' or an empty filename. The impact is modifying the permissions of the target directory on the client side. (CVE-2018-20685)
- Due to missing character encoding in the progress display, a malicious server can employ crafted object names to manipulate the client output, e.g., by using ANSI control codes to hide additional files being transferred. This affects 'refresh_progress_meter()' in progressmeter.c. (CVE-2019-6109)
- Due to accepting and displaying arbitrary stderr output from the server, a malicious server can manipulate the client output, for example to use ANSI control codes to hide additional files being transferred. (CVE-2019-6110)
- A malicious scp server can overwrite arbitrary files in the scp client target directory. If recursive operation (-r) is performed, the server can manipulate subdirectories as well (for example, to overwrite the .ssh/authorized_keys file). (CVE-2019-6111)
Solution
Upgrade to OpenSSH 8.x version 8.0 or later.See Also
Plugin Details
Severity: Medium
ID: 701156
Family: SSH
Published: 8/21/2019
Updated: 8/21/2019
Risk Information
CVSS v2
Risk Factor: Medium
Base Score: 4
Temporal Score: 3
Vector: AV:N/AC:H/Au:N/C:P/I:P/A:N
Temporal Vector: E:POC/RL:OF/RC:UR
CVSS v3
Risk Factor: Medium
Base Score: 6.8
Temporal Score: 6.2
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Temporal Vector: E:P/RL:U/RC:R
Vulnerability Information
CPE: cpe:/a:openbsd:openssh
Patch Publication Date: 1/31/2019
Vulnerability Publication Date: 1/31/2019
Reference Information
CVE: CVE-2018-20685, CVE-2019-6109, CVE-2019-6110, CVE-2019-6111