CVE-2009-2404 in Network Security Services
Summary
by MITRE
Heap-based buffer overflow in a regular-expression parser in Mozilla Network Security Services (NSS) before 3.12.3, as used in Firefox, Thunderbird, SeaMonkey, Evolution, Pidgin, and AOL Instant Messenger (AIM), allows remote SSL servers to cause a denial of service (application crash) or possibly execute arbitrary code via a long domain name in the subject s Common Name (CN) field of an X.509 certificate, related to the cert_TestHostName function.
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Analysis
by VulDB Data Team • 08/13/2021
The vulnerability identified as CVE-2009-2404 represents a critical heap-based buffer overflow within the regular-expression parser of Mozilla Network Security Services NSS library version 3.12.2 and earlier. This flaw affects multiple widely-used applications including Firefox web browser, Thunderbird email client, SeaMonkey suite, Evolution mail client, Pidgin instant messaging application, and AOL Instant Messenger. The vulnerability specifically manifests when processing X.509 certificates containing excessively long domain names in the Common Name field, creating a dangerous condition that can be exploited by remote attackers to compromise system integrity. The flaw occurs during certificate validation when the cert_TestHostName function processes certificate subject names, particularly those with domain names that exceed the allocated buffer space, leading to memory corruption that can result in application crashes or potentially arbitrary code execution.
The technical nature of this vulnerability stems from insufficient input validation within the NSS library's certificate parsing routines. When a remote SSL server presents a certificate containing a domain name that exceeds the predetermined buffer limits in the cert_TestHostName function, the regular-expression parser fails to properly handle the overflow condition. This results in memory corruption that can be leveraged to overwrite adjacent memory locations, potentially allowing an attacker to execute malicious code with the privileges of the affected application. The heap-based nature of the buffer overflow means that the corrupted memory exists in the heap portion of the application's memory space, making it particularly dangerous as it can affect the application's internal data structures and control flow mechanisms. This vulnerability directly maps to CWE-121, heap-based buffer overflow, and can be categorized under the broader ATT&CK technique T1059.007 for command and scripting interpreter, as the successful exploitation could lead to arbitrary code execution.
The operational impact of CVE-2009-2404 extends far beyond individual application compromises, affecting an entire ecosystem of software that relies on NSS for secure communications. The vulnerability's exploitation potential means that any user of the affected applications could be subjected to denial of service attacks that crash applications or, more critically, enable remote code execution attacks that could allow attackers to gain complete control over the victim's system. The widespread adoption of NSS across multiple platforms and applications means that the attack surface is extensive, potentially affecting millions of users globally. Organizations using these applications face significant risk as attackers can exploit this vulnerability through man-in-the-middle attacks or by compromising SSL servers that present malicious certificates. The vulnerability particularly affects web browsing and email applications where users frequently encounter SSL certificates from various sources, making it an attractive target for cybercriminals seeking to compromise user systems through seemingly legitimate certificate exchanges.
Mitigation strategies for CVE-2009-2404 primarily focus on immediate application updates and patches provided by vendors. System administrators should prioritize updating all affected applications to versions that include the NSS library fixes, with particular attention to Firefox 3.0.11 and later versions, Thunderbird 2.0.0.22 and later, and SeaMonkey 1.1.18 and later. The patch implementation addresses the buffer overflow by implementing proper bounds checking in the cert_TestHostName function and ensuring that domain name validation does not exceed allocated buffer space. Additional defensive measures include implementing certificate pinning policies where appropriate, monitoring for suspicious certificate issuance patterns, and employing network-level security controls such as SSL inspection appliances that can detect and block malformed certificates. Organizations should also consider implementing intrusion detection systems capable of identifying exploitation attempts targeting this specific vulnerability, as well as establishing incident response procedures for handling potential exploitation events. The vulnerability's remediation through version updates aligns with standard security practices outlined in NIST SP 800-128 for vulnerability management and patch deployment strategies.