CVE Vulnerabilities

CVE-2017-2911

Improper Validation of Certificate with Host Mismatch

Published: Nov 07, 2017 | Modified: Jun 13, 2022
CVSS 3.x
5.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 2.x
2.6 LOW
AV:N/AC:H/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

An exploitable vulnerability exists in the remote control functionality of Circle with Disney running firmware 2.0.1. SSL certificates for specific domain names can cause the rclient daemon to accept a different certificate than intended. An attacker can host an HTTPS server with this certificate to trigger this vulnerability.

Weakness

The product communicates with a host that provides a certificate, but the product does not properly ensure that the certificate is actually associated with that host.

Affected Software

Name Vendor Start Version End Version
Circle_with_disney_firmware Meetcircle 2.0.1 (including) 2.0.1 (including)

Extended Description

Even if a certificate is well-formed, signed, and follows the chain of trust, it may simply be a valid certificate for a different site than the site that the product is interacting with. If the certificate’s host-specific data is not properly checked - such as the Common Name (CN) in the Subject or the Subject Alternative Name (SAN) extension of an X.509 certificate - it may be possible for a redirection or spoofing attack to allow a malicious host with a valid certificate to provide data, impersonating a trusted host. In order to ensure data integrity, the certificate must be valid and it must pertain to the site that is being accessed. Even if the product attempts to check the hostname, it is still possible to incorrectly check the hostname. For example, attackers could create a certificate with a name that begins with a trusted name followed by a NUL byte, which could cause some string-based comparisons to only examine the portion that contains the trusted name. This weakness can occur even when the product uses Certificate Pinning, if the product does not verify the hostname at the time a certificate is pinned.

Potential Mitigations

References