CVE-2020-24661 Explained : Impact and Mitigation

GNOME Geary before 3.36.3 mishandles pinned TLS certificate verification for IMAP and SMTP services, potentially allowing interception of incoming and outgoing mail.

Understanding CVE-2020-24661

This CVE involves a vulnerability in GNOME Geary that could be exploited by a man-in-the-middle attacker to intercept email communications.

What is CVE-2020-24661?

CVE-2020-24661 refers to a security issue in GNOME Geary versions prior to 3.36.3, where TLS certificate verification for IMAP and SMTP services is not correctly handled.

The Impact of CVE-2020-24661

The vulnerability allows an attacker to present an invalid TLS certificate, such as a self-signed certificate, to intercept emails being sent or received by the user.

Technical Details of CVE-2020-24661

This section provides more in-depth technical information about the CVE.

Vulnerability Description

GNOME Geary before 3.36.3 does not properly verify TLS certificates for IMAP and SMTP services, enabling a man-in-the-middle attack to intercept email traffic.

Affected Systems and Versions

Product: GNOME Geary
Versions affected: Before 3.36.3

Exploitation Mechanism

The vulnerability arises when the client system does not utilize a system-provided PKCS#11 store, allowing an attacker to present a different invalid certificate to intercept mail.

Mitigation and Prevention

To address CVE-2020-24661, users and organizations should take immediate and long-term security measures.

Immediate Steps to Take

Update GNOME Geary to version 3.36.3 or newer to mitigate the vulnerability.
Configure the client system to use a system-provided PKCS#11 store for TLS certificate verification.

Long-Term Security Practices

Regularly update software and applications to patch known vulnerabilities.
Implement secure email protocols and encryption methods to protect email communications.

Patching and Updates

Stay informed about security advisories and updates from GNOME Geary to apply patches promptly.