OpenSSH < 8.0 Multiple Vulnerbilities

medium Nessus Network Monitor Plugin ID 701156
New! Plugin Severity Now Using CVSS v3

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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

http://www.openssh.com/txt/release-8.0

Plugin Details

Severity: Medium

ID: 701156

Family: SSH

Published: 8/21/2019

Updated: 8/21/2019

Dependencies: 1997

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 4

Temporal Score: 3

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N

Temporal Vector: CVSS2#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: CVSS:3.0/E:P/RL:U/RC:R

Vulnerability Information

CPE: cpe:2.3: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

BID: 106531, 106843