CVE-2009-2862 in IOS
Summary
by MITRE
The Object Groups for Access Control Lists (ACLs) feature in Cisco IOS 12.2XNB, 12.2XNC, 12.2XND, 12.4MD, 12.4T, 12.4XZ, and 12.4YA allows remote attackers to bypass intended access restrictions via crafted requests, aka Bug IDs CSCsx07114, CSCsu70214, CSCsw47076, CSCsv48603, CSCsy54122, and CSCsu50252.
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Analysis
by VulDB Data Team • 03/30/2025
The vulnerability described in CVE-2009-2862 represents a critical access control flaw within Cisco IOS software versions that affects the Object Groups for Access Control Lists functionality. This issue manifests in multiple release branches including 12.2XNB, 12.2XNC, 12.2XND, 12.4MD, 12.4T, 12.4XZ, and 12.4YA, indicating a widespread problem that impacts a significant portion of Cisco's network infrastructure software ecosystem. The vulnerability stems from improper validation of crafted requests that manipulate the Object Groups feature, which is designed to provide structured access control mechanisms for network devices. This flaw creates a pathway for remote attackers to circumvent the intended security controls that should restrict access to network resources based on predefined object groups and their associated access permissions.
The technical implementation of this vulnerability involves the manipulation of ACL object groups through carefully crafted network requests that exploit a logic flaw in the IOS processing of these access control elements. When the system processes these malformed requests, it fails to properly validate the object group references, allowing unauthorized access patterns to be interpreted as legitimate access requests. This type of vulnerability falls under CWE-284 which specifically addresses improper access control mechanisms, and represents a classic example of how object-oriented access control structures can be subverted through request manipulation. The attack vector is particularly concerning as it operates remotely, meaning that adversaries do not require physical access to the network device or local network credentials to exploit this weakness.
The operational impact of this vulnerability extends far beyond simple unauthorized access, as it fundamentally undermines the security posture of affected network devices. Network administrators who rely on ACL object groups for controlling traffic flow, protecting sensitive network segments, and implementing security policies face a scenario where their carefully configured access restrictions become ineffective. This compromise can lead to unauthorized network access, potential data exfiltration, and the ability to bypass network segmentation controls that are essential for maintaining security boundaries. The vulnerability affects network infrastructure components that are critical to enterprise and service provider networks, potentially allowing attackers to move laterally within network environments or gain access to sensitive systems that should be protected by these ACL mechanisms.
Mitigation strategies for this vulnerability require immediate attention from network administrators and security teams responsible for maintaining Cisco IOS devices. The most effective approach involves applying the vendor-supplied security patches and updates that address the specific logic flaw in the Object Groups processing within the affected IOS versions. Organizations should also consider implementing network segmentation measures and additional monitoring controls to detect anomalous traffic patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of maintaining up-to-date network security configurations and highlights the need for comprehensive vulnerability management processes that include regular assessment of network device software versions. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and lateral movement, as attackers can leverage the bypassed access controls to expand their network presence and access additional resources that were previously protected by the ACL object groups.