CVE-2021-40831
Assigner: F-SecureUS
Published: 2021-11-22T23:41:19
State: PUBLISHED
affected: platforms: macOS
product: AWS IoT Device SDK v2 for Java 
vendor: Amazon Web Services
versions: lessThan: 1.5.0
status: affected
version: unspecified
versionType: custom
platforms: macOS
product: AWS IoT Device SDK v2 for Python
vendor: Amazon Web Services
versions: lessThan: 1.7.0
status: affected
version: unspecified
versionType: custom
platforms: macOS
product: AWS IoT Device SDK v2 for C++
vendor: Amazon Web Services
versions: lessThan: 1.14.0
status: affected
version: unspecified
versionType: custom
platforms: macOS
product: AWS IoT Device SDK v2 for Node.js
vendor: Amazon Web Services
versions: lessThan: 1.6.0
status: affected
version: unspecified
versionType: custom
platforms: macOS
product: AWS-C-IO
vendor: Amazon Web Services
versions: status: affected
version: 0.10.7
credits: value: F-Secure
descriptions: value: The AWS IoT Device SDK v2 for Java, Python, C++ and Node.js appends a user supplied Certificate Authority (CA) to the root CAs instead of overriding it on macOS systems. Additionally, SNI validation is also not enabled when the CA has been “overridden”. TLS handshakes will thus succeed if the peer can be verified either from the user-supplied CA or the system’s default trust-store. Attackers with access to a host’s trust stores or are able to compromise a certificate authority already in the host's trust store (note: the attacker must also be able to spoof DNS in this case) may be able to use this issue to bypass CA pinning. An attacker could then spoof the MQTT broker, and either drop traffic and/or respond with the attacker's data, but they would not be able to forward this data on to the MQTT broker because the attacker would still need the user's private keys to authenticate against the MQTT broker. The 'aws_tls_ctx_options_override_default_trust_store_*' function within the aws-c-io submodule has been updated to address this behavior. This issue affects: Amazon Web Services AWS IoT Device SDK v2 for Java versions prior to 1.5.0 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Python versions prior to 1.7.0 on macOS. Amazon Web Services AWS IoT Device SDK v2 for C++ versions prior to 1.14.0 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Node.js versions prior to 1.6.0 on macOS. Amazon Web Services AWS-C-IO 0.10.7 on macOS.
metrics: cvssV3_1: attackComplexity: HIGH
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 6.3
baseSeverity: MEDIUM
confidentialityImpact: HIGH
integrityImpact: HIGH
privilegesRequired: HIGH
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H
version: 3.1
problemTypes: descriptions: description: The AWS IoT Device SDK v2 for Java, Python, C++ and Node.js appends a user supplied Certificate Authority (CA) to the root CAs instead of overriding it on macOS systems. Additionally, SNI validation is also not enabled when the CA has been “overridden”. TLS handshakes will thus succeed if the peer can be verified either from the user-supplied CA or the system’s default trust-store. Attackers with access to a host’s trust stores or are able to compromise a certificate authority already in the host's trust store (note: the attacker must also be able to spoof DNS in this case) may be able to use this issue to bypass CA pinning. An attacker could then spoof the MQTT broker, and either drop traffic and/or respond with the attacker's data, but they would not be able to forward this data on to the MQTT broker because the attacker would still need the user's private keys to authenticate against the MQTT broker. 
type: text
solutions: value: Update to the latest versions of the AWS IoT Device SDK.
source: discovery: INTERNAL
title: Missing SNI validation and inconsistent CA override function behavior within AWS IoT Device SDKs on Apple devices
x_generator: engine: Vulnogram 0.0.9