CVE-2007-4346 in Backupexec System Recovery
Summary
by MITRE
The Job Engine (bengine.exe) service in Symantec Backup Exec for Windows Servers (BEWS) 11d build 11.0.7170 and 11.0.6.6235 allows remote attackers to cause a denial of service (NULL dereference and service crash) via a crafted packet to port 5633/tcp.
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Analysis
by VulDB Data Team • 08/01/2019
The vulnerability identified as CVE-2007-4346 resides within Symantec Backup Exec for Windows Servers version 11d build 11.0.7170 and 11.0.6.6235 where the Job Engine service component bengine.exe fails to properly validate incoming network packets. This critical flaw manifests as a NULL pointer dereference condition that occurs when the service receives a specially crafted packet on TCP port 5633. The service process crashes immediately upon encountering this malformed input, resulting in a denial of service condition that disrupts backup operations and renders the backup server unavailable to legitimate users. The vulnerability represents a classic buffer overflow scenario where improper input validation leads to memory corruption and service termination.
The technical exploitation of this vulnerability follows a well-defined pattern that aligns with common remote attack methodologies. Attackers can send a malicious packet to port 5633 without requiring any authentication or privileged access, making this particularly dangerous in networked environments where the service is exposed to untrusted networks. The NULL dereference occurs during the packet processing routine within the bengine.exe service, where the application attempts to access memory at address zero, causing an immediate crash. This behavior directly correlates to CWE-476 which defines NULL pointer dereference as a condition where a null value is used as a pointer, leading to application termination or system instability.
From an operational impact perspective, this vulnerability creates significant business disruption for organizations relying on Symantec Backup Exec for Windows Servers. The denial of service condition affects not only the backup service but potentially the entire backup infrastructure, leading to extended downtime and possible data recovery delays. Network administrators face the challenge of maintaining backup operations while the service remains vulnerable, as the crash occurs immediately upon packet reception. The vulnerability also represents a potential entry point for more sophisticated attacks, as the service crash could be leveraged to create a persistent denial of service condition or serve as a stepping stone for additional exploitation attempts. This type of vulnerability commonly maps to ATT&CK technique T1499 which involves network denial of service attacks that disrupt services and can lead to data unavailability.
Organizations should implement immediate mitigations including network segmentation to restrict access to port 5633, firewall rules to block unauthorized connections, and network monitoring to detect suspicious packet patterns. The most effective long-term solution involves applying the vendor-provided security patches that address the input validation flaws in the bengine.exe service. System administrators should also consider disabling the Job Engine service if it is not actively required, as this reduces the attack surface. Regular vulnerability assessments and security monitoring should be implemented to identify similar issues in other backup and data protection software components. The vulnerability highlights the importance of secure coding practices and proper input validation in network services, particularly those handling untrusted network input. Organizations should also maintain updated incident response procedures to handle service disruptions caused by similar vulnerabilities.