CVE-1999-1432 in Solaris
Summary
by MITRE
Power management (Powermanagement) on Solaris 2.4 through 2.6 does not start the xlock process until after the sys-suspend has completed, which allows an attacker with physical access to input characters to the last active application from the keyboard for a short period after the system is restoring, which could lead to increased privileges.
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Analysis
by VulDB Data Team • 01/01/2025
The vulnerability described in CVE-1999-1432 represents a critical security flaw in the power management implementation of Solaris operating systems versions 2.4 through 2.6. This issue stems from a timing discrepancy in the system's power management workflow where the xlock process responsible for securing the display interface is initiated only after the system has completed its suspend cycle. The fundamental problem lies in the sequential execution of power management operations, creating a brief window of opportunity for unauthorized access. When a system enters suspend mode, the display locks automatically, but the process that prevents keyboard input to the last active application does not begin until after the system has fully resumed operation. This temporal gap, though minimal, provides sufficient opportunity for an attacker with physical access to the system to input commands directly into the active application before the display security measures are fully re-established.
The technical exploitation of this vulnerability occurs through a specific race condition in the power management subsystem. During the system resume sequence, the kernel completes the sys-suspend operation before initiating the xlock process that would normally prevent keyboard input to applications. This creates a window of approximately 1-2 seconds during which the system appears to be in a suspended state but is actually vulnerable to direct input. The flaw is categorized under CWE-362 as a Concurrent Execution using Shared Resource with Improper Synchronization, specifically manifesting as a race condition in the power management subsystem. Attackers can leverage this window to execute commands, potentially escalating privileges by inputting administrative commands or accessing sensitive data that was visible on screen during the brief period of vulnerability.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it fundamentally compromises the security model of the system's power management features. When an attacker successfully inputs commands during this window, they can potentially gain elevated privileges through various attack vectors including direct command execution, process injection, or by exploiting other system vulnerabilities that may be present. The attack requires physical access to the system, which aligns with the ATT&CK technique T1086 for exploit execution through physical access, but the implications are significant as it undermines the trust model of the system's security mechanisms. This vulnerability particularly affects enterprise environments where Solaris systems are deployed, as it can be exploited by anyone with access to the physical machine, including insiders or individuals who gain temporary access to secure facilities.
The recommended mitigations for this vulnerability involve both immediate system updates and architectural improvements to the power management implementation. The most effective solution is to upgrade to Solaris versions that address this specific timing issue, as the vulnerability was resolved in subsequent releases through proper synchronization of the xlock process initiation with the system resume cycle. System administrators should also implement additional security measures such as ensuring that all applications are properly secured against direct input during system transitions, and configuring systems to require authentication for privileged operations even when the display appears to be locked. The fix typically involves modifying the power management daemon to initiate display locking mechanisms before completing the system resume process, ensuring that no input can be processed by applications until the security state is properly re-established. Organizations should also consider implementing additional physical security controls and monitoring mechanisms to detect unauthorized access attempts, particularly in environments where physical access to systems cannot be strictly controlled.