CVE-2004-0354 in Anubis
Summary
by MITRE
Multiple format string vulnerabilities in GNU Anubis 3.6.0 through 3.6.2, 3.9.92 and 3.9.93 allow remote attackers to execute arbitrary code via format string specifiers in strings passed to (1) the info function in log.c, (2) the anubis_error function in errs.c, or (3) the ssl_error function in ssl.c.
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Analysis
by VulDB Data Team • 12/22/2024
The vulnerability identified as CVE-2004-0354 represents a critical format string vulnerability affecting GNU Anubis versions 3.6.0 through 3.6.2 and 3.9.92 through 3.9.93. This flaw exists within the core logging and error handling mechanisms of the email encryption and decryption software, creating a pathway for remote code execution through carefully crafted input strings that are processed without proper sanitization. The affected functions include the info function in log.c, the anubis_error function in errs.c, and the ssl_error function in ssl.c, all of which are integral to the application's operational logging and error reporting capabilities.
Format string vulnerabilities occur when application code uses user-supplied data as format strings without proper validation or sanitization, allowing attackers to inject format specifiers that can manipulate the program's execution flow. In the context of GNU Anubis, these vulnerabilities are particularly dangerous because they affect core functions that handle error reporting and logging operations, which are frequently invoked during normal application operation. The vulnerability manifests when the application processes strings containing format specifiers such as %s, %d, or %x in contexts where these specifiers are interpreted by the printf family of functions, enabling attackers to read from or write to arbitrary memory locations.
The operational impact of this vulnerability extends beyond simple code execution, as it allows remote attackers to potentially gain complete control over the affected system. Attackers can exploit these flaws to read sensitive memory contents, overwrite critical program variables, or inject malicious code that executes with the privileges of the running Anubis process. Given that GNU Anubis is designed for secure email handling, this vulnerability creates a significant security risk that could compromise encrypted communications and potentially provide attackers with access to sensitive email data. The vulnerability affects systems where Anubis is deployed as a mail filter or gateway, making it particularly concerning for enterprise email infrastructure.
Mitigation strategies for this vulnerability require immediate patching of affected GNU Anubis versions to the latest stable releases that address these format string issues. Organizations should also implement network segmentation and access controls to limit exposure of vulnerable systems, while monitoring for suspicious network activity that might indicate exploitation attempts. Security practitioners should consider implementing application-level protections such as stack canaries and address space layout randomization to reduce exploit reliability, though these measures are secondary to proper code fixes. The vulnerability aligns with CWE-134, which specifically addresses format string vulnerabilities, and represents a classic example of how improper input validation in logging functions can create severe security implications. From an ATT&CK perspective, this vulnerability maps to techniques involving code injection and privilege escalation, with potential for lateral movement if exploited on systems with elevated privileges, making comprehensive network monitoring and incident response procedures essential for organizations using affected software versions.