D-Link DWR-932B Telnet Service backdoor

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.1$0-$5k0.00

A vulnerability was found in D-Link DWR-932B (the affected version unknown) and classified as critical. Affected by this issue is an unknown part of the component Telnet Service. The manipulation with an unknown input leads to a backdoor vulnerability. Using CWE to declare the problem leads to CWE-912. The product contains functionality that is not documented, not part of the specification, and not accessible through an interface or command sequence that is obvious to the product's users or administrators. Impacted is confidentiality, integrity, and availability.

The bug was discovered 12/04/2015. The weakness was presented 09/28/2016 by Pierre Kim as not defined mailinglist post (Bugtraq). The advisory is shared for download at seclists.org. The exploitation is known to be easy. The attack may be launched remotely. A simple authentication is necessary for exploitation. Technical details are unknown but a public exploit is available. The MITRE ATT&CK project declares the attack technique as T1588.001. The following code is the reason for this vulnerability:

#Sandro { for telnetd debug...
start-stop-daemon -S -b -a /bin/logmaster
#if [ -e /config2/telnetd ]; then
		start-stop-daemon -S -b -a /sbin/telnetd
#fi
#Sandro }

A public exploit has been developed by Pierre Kim and been published immediately after the advisory. The exploit is available at packetstormsecurity.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 299 days. During that time the estimated underground price was around $25k-$100k.

It is possible to mitigate the problem by applying the configuration setting .Addressing this vulnerability is possible by firewalling tcp/23 (telnet). The best possible mitigation is suggested to be the change of configuration settings.

See 92229, 92230, 92231 and 92232 for similar entries.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.1

VulDB Base Score: 8.8
VulDB Temp Score: 8.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Backdoor
CWE: CWE-912
ATT&CK: T1588.001

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Pierre Kim
Download: 🔍
Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Config
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Firewalling: 🔍

Timelineinfo

12/04/2015 🔍
06/15/2016 +194 days 🔍
06/16/2016 +1 days 🔍
09/28/2016 +104 days 🔍
09/28/2016 +0 days 🔍
09/28/2016 +0 days 🔍
04/27/2019 +941 days 🔍

Sourcesinfo

Vendor: dlink.com

Advisory: seclists.org
Researcher: Pierre Kim
Status: Not defined
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 09/28/2016 16:47
Updated: 04/27/2019 17:33
Changes: 09/28/2016 16:47 (50), 04/27/2019 17:33 (1)
Complete: 🔍

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