CVE-2005-3934 in pcAnywhere
Summary
by MITRE
Buffer overflow in Symantec pcAnywhere 11.0.1, 11.5.1, and all other 32-bit versions allows remote attackers to cause a denial of service (application crash) via unknown attack vectors.
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Analysis
by VulDB Data Team • 06/28/2025
The vulnerability identified as CVE-2005-3934 represents a critical buffer overflow flaw affecting Symantec pcAnywhere versions 11.0.1, 11.5.1, and all other 32-bit implementations of the software. This vulnerability resides within the remote access and desktop sharing application that was widely deployed in enterprise environments for system administration and remote support operations. The flaw manifests as a classic buffer overflow condition that occurs when the application processes incoming data without proper bounds checking, allowing malicious actors to manipulate memory structures through carefully crafted input sequences. The affected versions of pcAnywhere were particularly concerning given their widespread deployment across corporate networks, making them attractive targets for exploitation.
The technical nature of this buffer overflow vulnerability falls under CWE-121, which specifically addresses stack-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations. The vulnerability operates through unknown attack vectors that likely involve manipulating network packets or data streams sent to the pcAnywhere service listening on standard ports. When exploited, the buffer overflow causes the application to crash and terminate unexpectedly, leading to denial of service conditions that can disrupt legitimate remote access operations. The 32-bit architecture limitations of these versions make them particularly susceptible to memory corruption attacks, as the addressing space constraints and memory management practices of the era provided fewer protections against such overflow conditions.
From an operational impact perspective, this vulnerability poses significant risks to organizations relying on Symantec pcAnywhere for critical system administration tasks. The denial of service condition can result in complete loss of remote access capabilities to affected systems, potentially requiring physical intervention or alternative access methods to restore service. Network administrators who depend on pcAnywhere for routine maintenance, troubleshooting, and system monitoring operations face substantial operational disruption when this vulnerability is exploited. The attack vectors remain unspecified in the public disclosure, which compounds the risk as defenders cannot properly prepare for specific exploitation techniques. The vulnerability affects both the client and server components of pcAnywhere, meaning that either endpoint could serve as an attack surface for triggering the buffer overflow condition.
Organizations should implement immediate mitigations including applying available patches from Symantec, which would have addressed the memory handling issues in the affected versions. Network segmentation and firewall rules should be configured to restrict access to pcAnywhere service ports to trusted networks only, limiting the attack surface for remote exploitation attempts. The principle of least privilege should be enforced by limiting the use of pcAnywhere to only essential administrative functions and implementing alternative secure remote access solutions. Monitoring network traffic for unusual patterns or malformed packets targeting pcAnywhere services can help detect potential exploitation attempts. Additionally, regular security assessments should verify that no unauthorized installations of the vulnerable versions exist within the network infrastructure, as these could serve as persistent attack vectors for lateral movement within the enterprise environment. The vulnerability demonstrates the critical importance of maintaining up-to-date security patches for remote access tools, as these applications often become prime targets for attackers seeking persistent access to corporate networks.