CVE-2018-21184 in D6100
Summary
by MITRE
Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects D6100 before 1.0.0.57, D7800 before 1.0.1.28, R7500v2 before 1.0.3.24, R7800 before 1.0.2.40, and R9000 before 1.0.3.6.
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Analysis
by VulDB Data Team • 06/03/2024
This vulnerability represents a critical stack-based buffer overflow condition that affects multiple NETGEAR networking devices including the D6100, D7800, R7500v2, R7800, and R9000 models. The flaw exists within the web interface authentication handling mechanism, where an authenticated user can exploit a buffer overflow by sending specially crafted input data to the affected devices. The vulnerability stems from inadequate input validation and bounds checking within the device's web server implementation, allowing malicious input to overwrite adjacent memory locations on the stack. This type of vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a serious weakness in software design and implementation. The attack vector requires an authenticated user context, meaning that an attacker must first establish valid credentials to access the device's web management interface before exploiting this vulnerability. The affected firmware versions demonstrate that this issue has persisted across multiple device generations and firmware releases, indicating a fundamental flaw in the development and testing processes rather than a one-time coding error.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as stack-based buffer overflows can potentially lead to arbitrary code execution on the affected devices. When an authenticated user sends malformed input to the vulnerable web interface, the buffer overflow can corrupt the stack memory structure, potentially allowing an attacker to overwrite return addresses, function pointers, or other critical execution data. This memory corruption can result in unpredictable behavior including system crashes, restarts, or more dangerously, provide a pathway for remote code execution. The implications are particularly concerning for networking equipment since these devices often serve as central points of network control and management. From an attack perspective, this vulnerability aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation, as it leverages authenticated access to escalate privileges and potentially gain deeper system control. The vulnerability affects devices that are commonly deployed in enterprise and home network environments, making them attractive targets for attackers seeking to establish persistent access or disrupt network operations.
Mitigation strategies for this vulnerability require immediate firmware updates from NETGEAR to address the buffer overflow conditions in the affected device models. Network administrators should prioritize updating all affected devices to the latest firmware versions that contain patches for this specific vulnerability. In addition to firmware updates, implementing network segmentation and access controls can help reduce the attack surface by limiting access to these management interfaces to authorized personnel only. The authentication requirements for these devices should be strengthened with multi-factor authentication where possible, and network monitoring should be implemented to detect anomalous access patterns or attempts to exploit the vulnerability. Organizations should also consider disabling unnecessary web management interfaces when not actively required for administration, as this reduces the potential attack vectors available to malicious actors. Security teams should monitor for any reported exploitation attempts or indicators of compromise related to these specific device models, as the vulnerability's impact can extend to broader network compromise when attackers successfully exploit the buffer overflow to gain elevated privileges. Regular security assessments of network infrastructure should include verification of firmware versions and patch compliance for all managed devices to prevent similar vulnerabilities from remaining unaddressed.