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AWS CDK RestApi not generating authorizationScope correctly in resultant CFN template

Moderate severity GitHub Reviewed Published Aug 27, 2024 in aws/aws-cdk • Updated Aug 28, 2024

Package

npm aws-cdk (npm)

Affected versions

>= 2.142.0, <= 2.148.0

Patched versions

2.148.1

Description

Summary

The AWS Cloud Development Kit (CDK) is an open-source framework for defining cloud infrastructure using code. Customers use it to create their own applications which are converted to AWS CloudFormation templates during deployment to a customer’s AWS account. CDK contains pre-built components called "constructs" that are higher-level abstractions providing defaults and best practices. This approach enables developers to use familiar programming languages to define complex cloud infrastructure more efficiently than writing raw CloudFormation templates.

We identified an issue in AWS Cloud Development Kit (CDK) which, under certain conditions, can result in granting authenticated Amazon Cognito users broader than intended access. Specifically, if a CDK application uses the "RestApi" construct with "CognitoUserPoolAuthorizer" as the authorizer and uses authorization scopes to limit access. This issue does not affect the availability of the specific API resources.

Impact

Authenticated Cognito users may gain unintended access to protected API resources or methods, leading to potential data disclosure, and modification issues.

Impacted versions: >=2.142.0;<=2.148.0

Patches

The patch is included in CDK version >=2.148.1.

Recommended Actions

  • Upgrade your AWS CDK version to 2.148.1 or newer and re-deploy your application(s) to address this issue.
  • If you are using older CDK versions before 2.142.0, you are not affected by this issue, however it is recommended to upgrade to the latest version to receive the latest features and fixes.
  • Confirm whether your application(s) is affected by searching for "CognitoUserPoolsAuthorizer" in your CDK application. If it is referenced inside the "RestApi" construct, and the "RestApi" resource or method utilize authorization scopes to limit access, and you deployed your applications using the impacted versions of CDK, your application is affected.

References

If you have any questions or comments about this advisory we ask that you contact AWS/Amazon Security via our vulnerability reporting page [1] or directly via email to [email protected]. Please do not create a public GitHub issue.

[1] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting

References

@super132 super132 published to aws/aws-cdk Aug 27, 2024
Published by the National Vulnerability Database Aug 27, 2024
Published to the GitHub Advisory Database Aug 27, 2024
Reviewed Aug 27, 2024
Last updated Aug 28, 2024

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v4 base metrics

Exploitability Metrics
Attack Vector Network
Attack Complexity Low
Attack Requirements None
Privileges Required Low
User interaction None
Vulnerable System Impact Metrics
Confidentiality None
Integrity None
Availability None
Subsequent System Impact Metrics
Confidentiality Low
Integrity Low
Availability None

CVSS v4 base metrics

Exploitability Metrics
Attack Vector: This metric reflects the context by which vulnerability exploitation is possible. This metric value (and consequently the resulting severity) will be larger the more remote (logically, and physically) an attacker can be in order to exploit the vulnerable system. The assumption is that the number of potential attackers for a vulnerability that could be exploited from across a network is larger than the number of potential attackers that could exploit a vulnerability requiring physical access to a device, and therefore warrants a greater severity.
Attack Complexity: This metric captures measurable actions that must be taken by the attacker to actively evade or circumvent existing built-in security-enhancing conditions in order to obtain a working exploit. These are conditions whose primary purpose is to increase security and/or increase exploit engineering complexity. A vulnerability exploitable without a target-specific variable has a lower complexity than a vulnerability that would require non-trivial customization. This metric is meant to capture security mechanisms utilized by the vulnerable system.
Attack Requirements: This metric captures the prerequisite deployment and execution conditions or variables of the vulnerable system that enable the attack. These differ from security-enhancing techniques/technologies (ref Attack Complexity) as the primary purpose of these conditions is not to explicitly mitigate attacks, but rather, emerge naturally as a consequence of the deployment and execution of the vulnerable system.
Privileges Required: This metric describes the level of privileges an attacker must possess prior to successfully exploiting the vulnerability. The method by which the attacker obtains privileged credentials prior to the attack (e.g., free trial accounts), is outside the scope of this metric. Generally, self-service provisioned accounts do not constitute a privilege requirement if the attacker can grant themselves privileges as part of the attack.
User interaction: This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable system. This metric determines whether the vulnerability can be exploited solely at the will of the attacker, or whether a separate user (or user-initiated process) must participate in some manner.
Vulnerable System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the VULNERABLE SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the VULNERABLE SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the VULNERABLE SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
Subsequent System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the SUBSEQUENT SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the SUBSEQUENT SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the SUBSEQUENT SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

EPSS score

0.045%
(17th percentile)

Weaknesses

CVE ID

CVE-2024-45037

GHSA ID

GHSA-qj85-69xf-2vxq

Source code

Credits

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