CVE-2017-2629 : Exploit Details and Defense Strategies

CVE-2017-2629 was published on July 27, 2018, affecting the curl version prior to 7.53.0. The vulnerability lies in the incorrect implementation of the TLS Certificate Status Request extension, potentially leading to users not being alerted to invalid server certificates.

Understanding CVE-2017-2629

CVE-2017-2629 is a medium-severity vulnerability impacting the curl software before version 7.53.0.

What is CVE-2017-2629?

The vulnerability in CVE-2017-2629 arises from a flaw in the code that checks the validity of a server's certificate using the TLS Certificate Status Request extension. This flaw causes the system to incorrectly assume the validity of the certificate, even when there is no valid proof or if the server does not support the TLS extension being checked. This oversight can mislead users into believing the server's security status is better than it actually is.

The Impact of CVE-2017-2629

The impact of CVE-2017-2629 includes:

Users may not be alerted to an invalid server certificate.
Users may be misled into thinking the server is more secure than it actually is.

Technical Details of CVE-2017-2629

CVE-2017-2629 has the following technical details:

Vulnerability Description

The vulnerability in curl before 7.53.0 incorrectly assesses the validity of server certificates, potentially leading to security misjudgments.

Affected Systems and Versions

Product: curl
Vendor: CURL
Versions Affected: 7.53.0

Exploitation Mechanism

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality Impact: None
Integrity Impact: Low
Availability Impact: None

Mitigation and Prevention

To address CVE-2017-2629, consider the following mitigation strategies:

Immediate Steps to Take

Update curl to version 7.53.0 or later to mitigate the vulnerability.
Regularly check for security advisories and updates from the vendor.

Long-Term Security Practices

Implement secure coding practices to prevent similar vulnerabilities.
Educate users on verifying server certificates manually.

Patching and Updates

Apply patches and updates promptly to ensure the security of the software.