Critical Buffer Overflow Vulnerability in D-Link Routers Poses Severe Security Risks
The Cybersecurity and Infrastructure Security Agency (CISA) has recently added a critical buffer overflow vulnerability affecting D-Link routers to its Known Exploited Vulnerabilities (KEV) catalog, signaling active exploitation in the wild. This flaw, identified as CVE-2022-37055, presents significant risks to organizations and enterprise networks utilizing the impacted D-Link networking equipment.
Understanding the Vulnerability
The root cause of this vulnerability lies in improper memory management within D-Link routers, which allows unauthenticated attackers to induce a buffer overflow condition. This flaw is classified under CWE-120: Buffer Copy without Checking Size of Input, a common and dangerous memory safety issue.
Technical Details:
– CVE ID: CVE-2022-37055
– Vulnerability Type: Buffer Overflow
– Affected Product: D-Link Routers
– CVSS v3.1 Score: 9.8 (Critical)
– Attack Vector: Network
– CWE Classification: CWE-120: Buffer Copy without Checking Size of Input
– Product Status: End-of-Life (EoL) / End-of-Service (EoS)
Implications of the Exploit
Successful exploitation of this vulnerability enables adversaries to execute arbitrary code with device-level privileges. This grants them complete control over network traffic, system integrity, and data confidentiality. The high Common Vulnerability Scoring System (CVSS) rating underscores the critical impact on the confidentiality, integrity, and availability (CIA) triad.
A particularly concerning aspect is that many of the affected D-Link products have reached end-of-life (EoL) or end-of-service (EoS) status. This means they no longer receive security updates from the vendor, leaving organizations with limited options for remediation. Legacy D-Link networking devices deployed across enterprise environments present persistent security gaps that attackers actively exploit to establish persistent network access and launch lateral movement campaigns.
CISA’s Advisory and Recommendations
CISA issued the advisory on December 8, 2025, with a mandatory remediation deadline of December 29, 2025. Organizations are urged to act swiftly to address this threat. The agency recommends applying vendor-supplied patches immediately where available. For organizations using end-of-support D-Link equipment without available mitigations, discontinuing the use of the equipment is the most viable security posture.
Understanding Buffer Overflow Vulnerabilities
The vulnerability relates to CWE-120 (Buffer Copy without Checking Size of Input), a well-documented memory safety flaw frequently exploited in network device attacks. Threat intelligence indicates that exploitation techniques are likely relatively straightforward, increasing the probability of widespread attack campaigns targeting exposed D-Link routers across internet-facing networks and less-secure corporate environments.
Recommended Actions for Network Administrators
Network administrators should prioritize inventory audits to identify all D-Link routers within their infrastructure, document their support status, and implement appropriate remediation strategies. Organizations must also review network segmentation controls to minimize lateral movement risks in the event of exploitation.
Implementing firewall rules that limit administrative access to routers and monitoring network traffic for suspicious device behavior provide additional defensive layers during the remediation window. Enterprises should follow applicable CISA Binding Operational Directive 22-01 guidance for cloud service deployments and assess whether affected equipment operates in critical infrastructure environments.
For those unable to apply patches or discontinue vulnerable products, implementing enhanced monitoring and access restrictions while developing equipment replacement timelines is advisable.
Conclusion
The discovery and active exploitation of CVE-2022-37055 in D-Link routers underscore the critical importance of proactive vulnerability management and timely remediation. Organizations must remain vigilant, especially when using devices that have reached EoL or EoS status, as these can become prime targets for attackers. By adhering to CISA’s recommendations and implementing robust security measures, organizations can mitigate the risks associated with this vulnerability and enhance their overall cybersecurity posture.
