Dropbear SSH Server < 2016.72 Multiple Vulnerabilities

critical Nessus Plugin ID 93650
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Synopsis

The SSH service running on the remote host is affected by multiple vulnerabilities.

Description

According to its self-reported version in its banner, Dropbear SSH running on the remote host is prior to 2016.74. It is, therefore, affected by the following vulnerabilities :

- A format string flaw exists due to improper handling of string format specifiers (e.g., %s and %x) in usernames and host arguments. An unauthenticated, remote attacker can exploit this to execute arbitrary code with root privileges. (CVE-2016-7406)

- A flaw exists in dropbearconvert due to improper handling of specially crafted OpenSSH key files. An unauthenticated, remote attacker can exploit this to execute arbitrary code. (CVE-2016-7407)

- A flaw exists in dbclient when handling the -m or -c arguments in scripts. An unauthenticated, remote attacker can exploit this, via a specially crafted script, to execute arbitrary code. (CVE-2016-7408)

- A flaw exists in dbclient or dropbear server if they are compiled with the DEBUG_TRACE option and then run using the -v switch. A local attacker can exploit this to disclose process memory. (CVE-2016-7409)

Solution

Upgrade to Dropbear SSH version 2016.74 or later.

See Also

https://matt.ucc.asn.au/dropbear/CHANGES

Plugin Details

Severity: Critical

ID: 93650

File Name: dropbear_ssh_74.nasl

Version: 1.5

Type: remote

Family: Misc.

Published: 9/22/2016

Updated: 11/14/2019

Dependencies: ssh_detect.nasl

Risk Information

CVSS Score Source: CVE-2016-7407

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:matt_johnston:dropbear_ssh_server

Exploit Ease: No known exploits are available

Patch Publication Date: 7/21/2016

Vulnerability Publication Date: 7/21/2016

Reference Information

CVE: CVE-2016-7406, CVE-2016-7407, CVE-2016-7408, CVE-2016-7409

BID: 92970, 92972, 92973, 92974