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CVE-2017-8227: Amcrest IPM-721S V2.420.AC00.16.R.20160909 devices have a timeout policy to wait for 5 minutes in case 30…
CVE-2017-8227 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists Amcrest Ipm 721s Firmware as the affected product. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
Amcrest IPM-721S V2.420.AC00.16.R.20160909 devices have a timeout policy to wait for 5 minutes in case 30 incorrect password attempts are detected using the Web and HTTP API interface provided by the device. However, if the same brute force attempt is performed using the ONVIF specification (which is supported by the same binary) then there is no account lockout or timeout executed. This can allow an attacker to circumvent the account protection mechanism and brute force the 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 performs the credential check in the binary for the ONVIF specification. If one opens this binary in IDA-pro one will notice that this follows a ARM little endian format. The function at address 00671618 in IDA pro is parses the WSSE security token header. The sub_ 603D8 then performs the authentication check and if it is incorrect passes to the function sub_59F4C which prints the value "Sender not authorized."
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Affected products
- Amcrest Ipm 721s Firmware: up to and including 2.420.ac00.16.r.20160909