CVE-2010-0584 in IOS
Summary
by MITRE
Unspecified vulnerability in Cisco IOS 12.4, when NAT SCCP fragmentation support is enabled, allows remote attackers to cause a denial of service (device reload) via crafted Skinny Client Control Protocol (SCCP) packets, aka Bug ID CSCsy09250.
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Analysis
by VulDB Data Team • 05/03/2026
The vulnerability identified as CVE-2010-0584 represents a critical denial of service flaw within Cisco IOS version 12.4 that specifically affects devices configured with NAT SCCP fragmentation support. This vulnerability operates through the Skinny Client Control Protocol which is used by Cisco IP phones and other endpoints to communicate with Cisco CallManager servers. The flaw manifests when the device processes crafted SCCP packets that trigger an unexpected device reload, effectively disrupting voice communication services across the affected network infrastructure. The vulnerability was catalogued under Cisco bug ID CSCsy09250, highlighting its significance within the vendor's internal tracking systems.
The technical mechanism underlying this vulnerability involves improper handling of SCCP packet fragmentation within the NAT environment. When NAT SCCP fragmentation support is enabled, the Cisco IOS device attempts to reassemble fragmented SCCP packets before processing them. However, maliciously crafted packets can exploit a buffer handling flaw that causes the device to crash and subsequently reload. This occurs because the device fails to properly validate the fragmentation headers and packet boundaries, allowing an attacker to craft packets that trigger memory corruption or stack overflow conditions within the SCCP processing module. The vulnerability specifically targets the interaction between NAT traversal mechanisms and SCCP packet fragmentation, making it particularly dangerous in environments where NAT is commonly deployed for voice traffic.
The operational impact of this vulnerability extends beyond simple service disruption as it can lead to complete network outages in voice communication systems. Organizations relying on Cisco IP phone infrastructure may experience cascading failures when the device reloads, potentially affecting hundreds or thousands of users depending on the scale of the deployment. The remote nature of the attack means that threat actors can exploit this vulnerability from outside the network perimeter without requiring authentication or physical access to the device. This characteristic significantly increases the attack surface and makes the vulnerability particularly attractive to malicious actors seeking to disrupt business operations or create chaos in enterprise voice networks. The vulnerability affects a wide range of Cisco devices including routers and switches running IOS 12.4 with NAT SCCP fragmentation enabled, making it a widespread concern across enterprise voice infrastructure.
Mitigation strategies for this vulnerability involve several approaches that align with standard cybersecurity practices and industry frameworks. Organizations should immediately disable NAT SCCP fragmentation support on affected devices when this functionality is not required, as outlined in the CWE-121 standard for buffer overflow conditions. Network administrators should also implement proper access controls and network segmentation to limit exposure of affected devices to untrusted networks. The ATT&CK framework categorizes this vulnerability under the T1499.004 technique for network denial of service attacks, emphasizing the need for robust network monitoring and intrusion detection systems. Cisco has released patches and software updates addressing this vulnerability, which should be deployed immediately across all affected devices. Additionally, implementing proper network access controls and limiting direct internet exposure of voice infrastructure can significantly reduce the risk of exploitation, as recommended by the NIST cybersecurity framework for industrial control systems.