CVE-2023-3674 : Exploit Details and Defense Strategies

This CVE-2023-3674 was published by Red Hat on July 19, 2023. It involves a vulnerability in Keylime that results in an attestation failure when the quote's signature does not validate.

Understanding CVE-2023-3674

This CVE identifies a flaw in the Keylime attestation verifier which fails to properly flag a device's TPM quote as faulty when the signature validation fails. This oversight could allow malicious actors to go undetected.

What is CVE-2023-3674?

The vulnerability in CVE-2023-3674 occurs in the Keylime attestation verifier, which does not mark a device's submitted TPM quote as faulty when the quote's signature fails to validate. Instead, it only issues an error in the log without designating the device as untrusted.

The Impact of CVE-2023-3674

The impact of this vulnerability is considered low, however, it poses a risk of allowing potential attacks to go unnoticed due to the failure to flag faulty TPM quotes.

Technical Details of CVE-2023-3674

This vulnerability has a CVSS v3.1 base score of 2.3, indicating a low severity level. The attack complexity is low, vector is local, no impact on availability, confidentiality impact is none, integrity impact is low, high privileges required, and user interaction is not needed.

Vulnerability Description

The flaw in the Keylime attestation verifier fails to mark a device as untrusted when the TPM quote's signature validation fails, potentially allowing malicious activities to go undetected.

Affected Systems and Versions

Keylime versions 7.2.5 and 7.3.0 are unaffected.
Keylime version 7.4.0 and above are affected.
Red Hat Enterprise Linux 9 with Keylime installed is affected.
Fedora systems with Keylime installed are also affected.

Exploitation Mechanism

Exploiting this vulnerability requires the ability to submit a manipulated TPM quote with a signature that does not validate, allowing an attacker to bypass proper attestation checks.

Mitigation and Prevention

To address CVE-2023-3674, immediate actions and long-term security practices are essential to mitigate the risk posed by this vulnerability.

Immediate Steps to Take

Red Hat and affected users should apply the necessary patches provided by Keylime to address this flaw promptly.
Organizations should monitor for any suspicious activities related to attestation failures within their systems.

Long-Term Security Practices

Regularly update and patch Keylime to ensure all known vulnerabilities are addressed.
Implement proper monitoring and logging mechanisms to detect any irregularities in the attestation process.

Patching and Updates

It is crucial for users of Keylime, especially in Red Hat Enterprise Linux 9 and Fedora systems, to apply the latest patches released by Keylime to address the flaw and enhance the security of their systems.