CVE-2006-2789 in Evolution
Summary
by MITRE
Evolution 2.2.x and 2.3.x in GNOME 2.7 and 2.8, when "load images if sender in addressbook" is enabled, allows remote attackers to cause a denial of service (persistent crash) via a crafted "From" header that triggers an assert error in camel-internet-address.c when a null pointer is used.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 07/12/2021
The vulnerability described in CVE-2006-2789 represents a critical denial of service flaw within the Evolution email client version 2.2.x and 2.3.x that was prevalent in GNOME 2.7 and 2.8 environments. This issue specifically manifests when the email client's configuration enables automatic image loading for senders who are present in the user's address book. The flaw operates through a carefully crafted malicious "From" header field that, when processed by the email client, triggers an assertion error within the camel-internet-address.c component of the underlying messaging library. This particular vulnerability falls under the CWE-119 category of "Improper Access to Memory Location" and demonstrates a classic null pointer dereference vulnerability that can be exploited to crash the application.
The technical execution of this vulnerability involves the exploitation of a null pointer dereference condition within the camel-internet-address.c source file where the application attempts to access memory through a null pointer reference. When a remote attacker crafts an email message with a maliciously formatted "From" header, the Evolution client's address parsing mechanism fails to properly validate the input, leading to a situation where a null pointer is passed to a function that expects a valid memory reference. This assertion failure causes the application to terminate unexpectedly, resulting in a persistent crash that forces users to restart the email client manually. The vulnerability is particularly concerning because it operates at the protocol level where email headers are processed, making it difficult to prevent through standard user interface controls or simple configuration changes.
The operational impact of this vulnerability extends beyond simple service disruption as it creates a persistent denial of service condition that can be repeatedly triggered by attackers. The crash occurs during normal email processing operations, meaning that users cannot simply avoid the issue by not opening certain emails or by changing their security settings. This vulnerability affects the core functionality of the Evolution email client and can be exploited in a variety of scenarios including mass mailing campaigns or targeted attacks against specific users. The persistence of the crash means that even after the initial exploitation, the application may not recover properly without manual intervention, potentially leading to extended downtime for users who rely on the email client for their daily operations. This vulnerability aligns with ATT&CK technique T1499.004 for "Endpoint Denial of Service" and represents a significant threat to email client stability in enterprise environments where Evolution is commonly deployed.
Mitigation strategies for this vulnerability require immediate application of security patches provided by the GNOME project and the Evolution development team, as well as temporary configuration changes that disable the problematic image loading feature. Organizations should implement email filtering rules that sanitize "From" header fields or disable automatic image loading for all email sources to prevent exploitation. System administrators should consider implementing monitoring solutions to detect repeated crash patterns that may indicate exploitation attempts. The vulnerability also highlights the importance of input validation and proper error handling in email processing applications, particularly in components that handle address parsing and validation. Security teams should conduct regular vulnerability assessments of email client configurations and ensure that all system components are kept up to date with the latest security patches to prevent similar issues from occurring in the future.