CVE-2004-0104 in Metamail
Summary
by MITRE
Multiple format string vulnerabilities in Metamail 2.7 and earlier allow remote attackers to execute arbitrary code.
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Analysis
by VulDB Data Team • 12/25/2024
The vulnerability identified as CVE-2004-0104 represents a critical format string flaw affecting Metamail version 2.7 and earlier implementations. This vulnerability resides within the email handling component of Metamail, which processes and displays email attachments and messages containing formatted content. Format string vulnerabilities occur when application code improperly handles user-supplied input during string formatting operations, allowing attackers to manipulate the format string itself rather than the data being formatted. The flaw specifically manifests when Metamail processes email headers or content that contains maliciously crafted format specifiers, potentially leading to arbitrary code execution on the target system.
The technical exploitation of this vulnerability leverages the fundamental weakness in how Metamail handles format strings during message processing. When the application encounters a format string specifier such as %s, %d, or %x in untrusted input, it fails to properly validate or sanitize these elements before passing them to functions like printf or sprintf. This oversight creates opportunities for attackers to inject malicious format specifiers that can read from memory locations, overwrite function pointers, or execute arbitrary code. The vulnerability is particularly dangerous because it can be triggered through email headers or attachment content, making it exploitable via standard email communication channels without requiring user interaction beyond opening the malicious message.
Operationally, this vulnerability presents significant risk to organizations relying on Metamail for email processing, as it enables remote code execution capabilities that can be exploited by attackers without physical access to the system. The impact extends beyond simple privilege escalation, as successful exploitation can lead to complete system compromise, data exfiltration, or deployment of additional malware. Attackers can leverage this vulnerability to establish persistent backdoors, escalate privileges, or use the compromised system as a launch point for further attacks within the network infrastructure. The vulnerability's remote exploitability means that threat actors can target systems from anywhere on the internet, making it particularly dangerous for organizations with limited network segmentation or robust email filtering mechanisms.
Security mitigations for CVE-2004-0104 should prioritize immediate patching of Metamail installations to versions that properly validate and sanitize format string inputs. Organizations should implement comprehensive email filtering solutions that scan for suspicious format string patterns in incoming messages, particularly in email headers and attachments. Network segmentation and firewall rules can help limit the potential impact of successful exploitation by restricting access to critical systems. Additionally, system hardening measures including disabling unnecessary email processing features and implementing strict input validation for all email content can reduce the attack surface. The vulnerability aligns with CWE-134 which specifically addresses format string vulnerabilities, and its exploitation patterns correspond to techniques documented in the ATT&CK framework under T1059 for command and scripting interpreter and T1078 for valid accounts. Organizations should also consider implementing intrusion detection systems capable of identifying suspicious format string patterns in network traffic and email content to provide additional layers of defense against this type of attack.