CVE-2001-0548 in Solaris
Summary
by MITRE
Buffer overflow in dtmail in Solaris 2.6 and 7 allows local users to gain privileges via the MAIL environment variable.
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Analysis
by VulDB Data Team • 01/04/2025
The vulnerability identified as CVE-2001-0548 represents a critical buffer overflow flaw within the dtmail component of Solaris operating systems version 2.6 and 7. This issue specifically affects the desktop mail application that was part of the Solaris Desktop Environment, creating a pathway for local attackers to escalate their privileges on affected systems. The vulnerability stems from improper input validation within the MAIL environment variable handling mechanism, which allows maliciously crafted input to overflow allocated buffer space and potentially execute arbitrary code with elevated privileges.
This buffer overflow vulnerability operates through the manipulation of the MAIL environment variable, which is typically used by mail applications to determine the user's mail spool location or other mail-related configurations. When dtmail processes this environment variable without adequate bounds checking, it fails to validate the length of input data, allowing an attacker to provide input that exceeds the allocated buffer capacity. The technical implementation of this flaw aligns with CWE-121, which describes heap-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations.
The operational impact of this vulnerability is significant as it enables local privilege escalation attacks that can potentially allow attackers to execute code with the privileges of the target user or even the root user if the application runs with elevated permissions. Attackers can exploit this by carefully crafting the MAIL environment variable to overwrite return addresses or other critical memory locations, effectively redirecting program execution flow. This type of attack falls under the ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation', and demonstrates how local users can leverage application flaws to gain unauthorized access to system resources.
Systems running Solaris 2.6 and 7 with the dtmail component are particularly vulnerable to this attack vector, as these versions contain the specific code path that fails to validate environment variable lengths properly. The vulnerability's exploitation requires local access to the system, making it a local privilege escalation issue rather than a remote attack vector. However, the impact remains severe as it allows attackers who already have user-level access to potentially gain root privileges, which could lead to complete system compromise. Organizations should note that this vulnerability is classified as a classic buffer overflow that can be exploited through environment variable manipulation, representing a common attack pattern that has been documented in numerous security advisories over the years.
Mitigation strategies for CVE-2001-0548 include applying the appropriate security patches released by Sun Microsystems for Solaris 2.6 and 7, which address the buffer overflow by implementing proper bounds checking for environment variable handling. System administrators should also consider implementing environment variable restrictions and monitoring for unusual MAIL variable values that might indicate exploitation attempts. Additionally, the principle of least privilege should be enforced by limiting local user access to system resources and ensuring that applications like dtmail do not run with unnecessary elevated privileges. The vulnerability highlights the importance of proper input validation in application code and demonstrates how seemingly minor implementation flaws in desktop applications can create significant security risks in enterprise environments.