CVE-2019-12098 : Security Advisory and Response

A man-in-the-middle attack is possible in the client side of Heimdal versions prior to 7.6.0 if the validation of anonymous PKINIT PA-PKINIT-KX key exchange fails. This vulnerability specifically exists in the krb5_init_creds_step function within the lib/krb5/init_creds_pw.c file.

Understanding CVE-2019-12098

In the client side of Heimdal before version 7.6.0, a security flaw allows a man-in-the-middle attack to occur due to the failure to verify anonymous PKINIT PA-PKINIT-KX key exchange.

What is CVE-2019-12098?

This CVE refers to a vulnerability in Heimdal versions prior to 7.6.0 that enables a man-in-the-middle attack when the validation of anonymous PKINIT PA-PKINIT-KX key exchange is not properly executed.

The Impact of CVE-2019-12098

The vulnerability can lead to unauthorized interception of communication and potential exposure of sensitive data to malicious actors.

Technical Details of CVE-2019-12098

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

The issue lies in the krb5_init_creds_step function within the lib/krb5/init_creds_pw.c file, allowing for a man-in-the-middle attack.

Affected Systems and Versions

Heimdal versions prior to 7.6.0 are affected by this vulnerability.

Exploitation Mechanism

The vulnerability arises when the validation of anonymous PKINIT PA-PKINIT-KX key exchange fails, creating an opportunity for malicious actors to intercept communication.

Mitigation and Prevention

Protecting systems from CVE-2019-12098 requires immediate actions and long-term security measures.

Immediate Steps to Take

Update Heimdal to version 7.6.0 or newer to mitigate the vulnerability.
Monitor network traffic for any signs of unauthorized access or interception.

Long-Term Security Practices

Implement strong encryption protocols to secure communication channels.
Regularly update and patch software to address known security issues.

Patching and Updates

Apply patches provided by Heimdal to fix the vulnerability and enhance system security.