CVE-2003-0776 in SANE
Summary
by MITRE
saned in sane-backends 1.0.7 and earlier does not properly "check the validity of the RPC numbers it gets before getting the parameters," with unknown consequences.
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Analysis
by VulDB Data Team • 06/12/2019
The vulnerability identified as CVE-2003-0776 affects the saned component within sane-backends version 1.0.7 and earlier, representing a critical flaw in the Scanner Access Now Easy (SANE) backend system. This issue specifically targets the RPC (Remote Procedure Call) number validation mechanism that governs communication between scanning clients and the saned daemon. The vulnerability arises from insufficient input validation where the system fails to properly verify the legitimacy of RPC numbers received during network communication, creating a potential pathway for malicious exploitation.
The technical flaw stems from inadequate parameter validation within the RPC processing pipeline of the saned daemon. When remote clients attempt to establish scanning sessions through the SANE network interface, the daemon receives RPC numbers that should be validated against expected ranges and formats. However, the vulnerable implementation fails to perform comprehensive checks on these RPC identifiers, allowing potentially malformed or malicious RPC numbers to proceed unchecked into the parameter processing stage. This weakness creates opportunities for buffer overflows, memory corruption, or arbitrary code execution depending on how the system handles these unvalidated inputs.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it could enable remote attackers to gain unauthorized access to scanning systems or compromise the integrity of the underlying operating environment. When the saned daemon processes unvalidated RPC numbers, it may inadvertently execute code or manipulate memory structures in ways that were not intended by the original software design. This vulnerability particularly affects networked scanning environments where multiple clients connect to a central scanning server, as the attack surface expands to include all network-accessible RPC endpoints. The unknown consequences mentioned in the original description suggest that the specific exploitation vectors and payload delivery mechanisms remain partially understood, which increases the risk profile significantly.
Mitigation strategies should focus on immediate patching of the sane-backends software to version 1.0.8 or later, which contains the necessary RPC validation fixes. System administrators should also implement network segmentation to limit access to saned services, restrict RPC number ranges through firewall rules, and monitor network traffic for anomalous RPC patterns. The vulnerability aligns with CWE-129, which addresses improper validation of array indices, and may relate to ATT&CK techniques involving remote code execution and privilege escalation. Organizations should also consider implementing intrusion detection systems to monitor for suspicious RPC number patterns and establish secure scanning practices that limit exposure to untrusted networks. Proper input validation and sanitization of all network-received parameters should be enforced throughout the SANE backend architecture to prevent similar issues from emerging in future versions.