CVE-2015-2819 in SQL Anywhere
Summary
by MITRE
SAP Sybase SQL Anywhere 11 and 16 allows remote attackers to cause a denial of service (crash) via a crafted request, aka SAP Security Note 2108161.
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Analysis
by VulDB Data Team • 06/25/2017
SAP Sybase SQL Anywhere versions 11 and 16 contain a critical vulnerability that enables remote attackers to execute a denial of service attack resulting in system crashes. This vulnerability stems from insufficient input validation mechanisms within the database engine's request processing pipeline, allowing malicious actors to craft specially formatted requests that trigger unexpected behavior in the software's memory management and execution flow. The flaw specifically manifests when the system processes malformed or unexpected data structures in database connection requests, leading to abrupt termination of database services and complete service unavailability. The vulnerability is particularly concerning as it affects widely deployed enterprise database systems where uptime and reliability are critical business requirements.
The technical implementation of this vulnerability involves the exploitation of buffer handling inconsistencies and inadequate error recovery mechanisms within the SQL Anywhere network protocol handler. When processing crafted requests containing malformed data sequences, the system fails to properly validate input parameters before attempting to parse and execute database operations. This leads to memory corruption scenarios where stack or heap corruption occurs during request processing, ultimately causing the database service to terminate unexpectedly. The vulnerability operates at the application layer and requires no authentication or privileged access, making it particularly dangerous as any remote user can exploit this weakness to disrupt database availability. The flaw aligns with CWE-121, which describes heap-based buffer overflow conditions, and represents a classic example of improper input validation leading to system instability.
The operational impact of this vulnerability extends beyond simple service disruption to encompass significant business continuity risks for organizations relying on SAP Sybase SQL Anywhere. Database crashes can result in immediate loss of application availability, data access interruptions, and potential data consistency issues during restart operations. The vulnerability affects both SQL Anywhere 11 and 16 versions, indicating a persistent flaw in the codebase that has not been adequately addressed in the affected releases. Organizations utilizing these database versions face potential downtime costs, service level agreement violations, and increased operational overhead from emergency response activities. The remote exploitability means that attackers can target these systems from external networks without requiring physical access or insider knowledge, amplifying the threat surface and making the vulnerability particularly attractive to cybercriminals seeking to disrupt business operations. This weakness maps to attack techniques in the MITRE ATT&CK framework under the service stop category, specifically targeting availability through system crash exploitation.
Mitigation strategies for this vulnerability should focus on immediate patch application as provided by SAP through Security Note 2108161, which contains the official remediation procedures for affected versions. Organizations should prioritize updating their SQL Anywhere installations to patched versions that address the input validation deficiencies in the network protocol handlers. Network segmentation and access controls can provide temporary defense-in-depth measures by limiting exposure of database systems to untrusted networks, though these should not be considered permanent solutions. Implementing robust monitoring and alerting systems around database service availability can help detect exploitation attempts and provide early warning of potential attacks. Additionally, organizations should conduct thorough vulnerability assessments of their database environments to identify other potential weaknesses that could be exploited in conjunction with this denial of service vulnerability. The remediation process should include comprehensive testing of patched systems to ensure that the vulnerability has been fully addressed without introducing regressions in database functionality or application compatibility.