Vulnerability Note VU#800094

Dahua Security DVRs contain multiple vulnerabilities

Original Release date: 13 Sep 2013 | Last revised: 04 Dec 2013

Overview

Digital video recorders (DVR) produced by Dahua Technology Co., Ltd. contain multiple vulnerabilities that could allow a remote attacker to gain privileged access to the devices.

Description

Dahua Technologies Co., Ltd. produces DVR appliances that contain multiple vulnerabilities.

CWE-798: Use of Hard-coded Credentials - CVE-2013-3612
All DVRs of the same series ship with the same default root password on a read-only partition. Therefore, the root password can only be changed by flashing the firmware. Additionally, a separate hard-coded remote backdoor account exists that can be used to control cameras and other system components remotely. It is only accessible if authorization is done through ActiveX or the stand-alone client. Additionally, a hash of the current date can be used as a master password to gain access to the system and reset the administrator's password.

CWE-294: Authentication Bypass by Capture-reply - CVE-2013-3613
The DVR appliance accepts UPnP requests from external untrusted devices. This can cause the telnet port of a DVR appliance to be automatically forwarded and accessible by external parties. These default conditions could allow an external attacker to detect the device and authenticate using the hard-coded credentials.

CWE-521: Weak Password Requirements - CVE-2013-3614
The device enforces insufficient password requirements. User passwords are limited to only six characters in length, making them computationally feasible to discover using brute-force methods.

CWE-916: Use of Password Hash with Insufficient Computational Effort - CVE-2013-3615
User passwords are hashed with a weak 48-bit algorithm, and are therefore susceptible to brute-force attacks within a reasonable amount of time.

The CVSS score reflects CVE-2013-3612.

Dahua has disputed some of these vulnerabilities. Please see Dahua's vendor information for details.

Impact

An unauthenticated remote attacker could gain privileged access to the device and compromise the confidentiality and integrity of its data. Additionally, the attacker could cause a denial-of-service.

Solution

We are currently unaware of a practical solution to this problem. Please consider the following workarounds.

Restrict Access

If possible, restrict access to the device using IP access lists and block UPnP requests from untrusted external devices.

Vendor Information (Learn More)

VendorStatusDate NotifiedDate Updated
Dahua SecurityUnknown09 Jul 201304 Dec 2013
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base 10.0 AV:N/AC:L/Au:N/C:C/I:C/A:C
Temporal 7.3 E:U/RL:W/RC:UC
Environmental 1.8 CDP:ND/TD:L/CR:ND/IR:ND/AR:ND

References

Credit

Thanks to Andrey Bezborodov, Kirill Ermakov, Alexander Raspopov, and Dmitry Sklyarov of Positive Technologies for reporting these vulnerabilities.

This document was written by Todd Lewellen.

Other Information

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