Vulnerability identifier: #VU309

Vulnerability risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-134

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Dropbear
Server applications / Remote management servers, RDP, SSH

Vendor: Matt Johnston

Description

The vulnerability allows a remote authenticated attacker to execute arbitrary code on the target system.

The vulnerability exists due to a format string error when handling usernames, containing format string characters (e.g. %) in getpwnam() function. A remote attacker with the ability to manipulate his username can execute arbitrary code on the target system.

Successful exploitation may allow an attacker to gain complete control over the vulnerable system.

Mitigation
Update to the latest version 2016.74.

Vulnerable software versions

Dropbear: 2013.56 - 2016.73

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External links
http://matt.ucc.asn.au/dropbear/CHANGES

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.