CVE-2007-3771 in Norton Antivirus
Summary
by MITRE
Stack-based buffer overflow in the Internet E-mail Auto-Protect feature in Symantec AntiVirus Corporate Edition before 10.1, and Client Security before 3.1, allows local users to cause a denial of service (service crash) via a long (1) To, (2) From, or (3) Subject header in an outbound SMTP e-mail message. NOTE: the original vendor advisory referenced CVE-2006-3456, but this was an error.
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Analysis
by VulDB Data Team • 06/07/2025
The vulnerability described in CVE-2007-3771 represents a critical stack-based buffer overflow affecting Symantec's antivirus software ecosystem, specifically targeting the Internet E-mail Auto-Protect feature within Symantec AntiVirus Corporate Edition versions prior to 10.1 and Client Security versions prior to 3.1. This flaw resides in the email processing mechanism that handles outbound SMTP messages, creating a potential vector for denial of service attacks that could disrupt critical email services within corporate environments. The vulnerability manifests when the software processes email headers containing excessively long data strings in the To, From, or Subject fields, exploiting memory management weaknesses in the email protection subsystem.
The technical implementation of this vulnerability stems from inadequate input validation within the email header processing routines of Symantec's antivirus software. When an email message with overly long header values is processed, the software fails to properly bounds-check the data before copying it into fixed-size stack buffers, leading to memory corruption that can cause the antivirus service to crash. This type of stack-based buffer overflow directly corresponds to CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent stack memory. The flaw operates at the application layer of the network stack, specifically within the email filtering and protection components that are designed to scan and analyze outgoing email traffic for potential threats.
The operational impact of this vulnerability extends beyond simple service disruption, as it can severely compromise email availability within enterprise environments where Symantec antivirus solutions are deployed. Local users with access to the system can exploit this weakness to cause intentional service crashes, potentially disrupting business operations and creating opportunities for more sophisticated attacks. The denial of service condition affects the email protection functionality itself, meaning that legitimate email traffic may be blocked or delayed while the service recovers from crashes, creating cascading effects throughout the organization's communication infrastructure. This vulnerability also demonstrates the importance of proper input validation in security software, as the antivirus protection mechanisms themselves become vulnerable to exploitation.
Organizations affected by this vulnerability should implement immediate mitigations including updating to the patched versions of Symantec AntiVirus Corporate Edition 10.1 and Client Security 3.1, which contain proper bounds checking and input validation mechanisms. Network administrators should also consider implementing additional email filtering layers that can detect and prevent malformed email headers from reaching the vulnerable antivirus systems. The remediation process must include thorough testing of updated software configurations to ensure that legitimate email processing continues to function properly while the buffer overflow protections are in place. Security monitoring should be enhanced to detect unusual patterns of service crashes that may indicate exploitation attempts, and incident response procedures should be updated to address potential denial of service scenarios involving email protection services. This vulnerability aligns with ATT&CK technique T1499.004, which covers network denial of service attacks, and demonstrates how security tools themselves can become attack vectors when proper input validation is not implemented.