CVE-2017-8229 Information

Description

Amcrest IPM-721S V2.420.AC00.16.R.20160909 devices allow an unauthenticated attacker to download the administrative credentials. If the firmware version V2.420.AC00.16.R 9/9/2016 is dissected using binwalk tool one obtains a _user-x.squashfs.img.extracted archive which contains the filesystem set up on the device that many of the binaries in the /usr folder. The binary \sonia\ is the one that has the vulnerable function that sets up the default credentials on the device. If one opens this binary in IDA-pro one will notice that this follows a ARM little endian format. The function sub_436D6 in IDA pro is identified to be setting up the configuration for the device. If one scrolls to the address 0x000437C2 then one can see that /current_config is being set as an ALIAS for /mnt/mtd/Config folder on the device. If one TELNETs into the device and navigates to /mnt/mtd/Config folder one can observe that it contains various files such as Account1 Account2 SHAACcount1 etc. This means that if one navigates to http://[IPofcamera]/current_config/Sha1Account1 then one should be able to view the content of the files. The security researchers assumed that this was only possible only after authentication to the device. However when unauthenticated access tests were performed for the same URL as provided above it was observed that the device file could be downloaded without any authentication.

CVSS Vector

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

Reference

http://packetstormsecurity.com/files/153224/Amcrest-IPM-721S-Credential-Disclosure-Privilege-Escalation.html https://github.com/ethanhunnt/IoT_vulnerabilities/blob/master/Amcrest_sec_issues.pdf https://seclists.org/bugtraq/2019/Jun/8

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8