CVE-2008-4070 in Thunderbird
Summary
by MITRE
Heap-based buffer overflow in Mozilla Thunderbird before 2.0.0.17 and SeaMonkey before 1.1.12 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a long header in a news article, related to "canceling [a] newsgroup message" and "cancelled newsgroup messages."
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Analysis
by VulDB Data Team • 08/17/2019
The vulnerability identified as CVE-2008-4070 represents a critical heap-based buffer overflow affecting Mozilla Thunderbird versions prior to 2.0.0.17 and SeaMonkey versions prior to 1.1.12. This flaw resides in the handling of newsgroup messages within the email client's message processing subsystem, specifically when dealing with header data during the cancellation of newsgroup messages. The vulnerability stems from inadequate bounds checking when processing excessively long header fields in news articles, creating an exploitable condition that can be triggered through malformed message data received from remote sources.
The technical implementation of this vulnerability involves the improper handling of memory allocation during the processing of newsgroup message headers. When Thunderbird or SeaMonkey encounters a newsgroup message with an unusually long header field, the application fails to properly validate the length of the header data before attempting to copy it into a fixed-size heap buffer. This classic buffer overflow condition occurs because the software does not perform sufficient input validation or boundary checking on the header length, allowing an attacker to provide header data that exceeds the allocated buffer size. The flaw specifically manifests during the "canceling a newsgroup message" and "cancelled newsgroup messages" operations, which are part of the standard news article processing workflow in these email clients.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable remote code execution on affected systems. Attackers can craft malicious newsgroup messages with oversized header fields that, when processed by the vulnerable email client, trigger the buffer overflow condition. This exploitation can result in application crashes that constitute a denial of service, but more critically, the heap corruption can be leveraged to execute arbitrary code with the privileges of the affected user. The vulnerability affects systems running the vulnerable versions of Thunderbird and SeaMonkey, which were widely deployed email clients in 2008, making the potential attack surface substantial. The flaw is particularly dangerous because it can be triggered automatically when users receive newsgroup messages, requiring no user interaction beyond normal email processing.
Mitigation strategies for this vulnerability require immediate patching of affected software versions to the patched releases that address the buffer overflow condition. Organizations should prioritize updating Thunderbird to version 2.0.0.17 or later and SeaMonkey to version 1.1.12 or later, which contain the necessary memory boundary checks and input validation fixes. System administrators should implement network-level controls to filter or block potentially malicious newsgroup messages, particularly those with unusually long header fields. The vulnerability aligns with CWE-121 heap-based buffer overflow and can be categorized under ATT&CK technique T1203 for legitimate program execution, as it exploits the normal operation of email client message processing. Additionally, the vulnerability demonstrates characteristics of T1059 for command and scripting interpreter usage, as successful exploitation could enable attackers to execute malicious code through compromised client processes. Security monitoring should focus on detecting unusual message processing patterns and potential crash events in email client applications, while regular security updates and patch management procedures should be enforced to prevent similar vulnerabilities from being exploited in the future.