CVE-2014-3299 in IOS
Summary
by MITRE
Cisco IOS allows remote authenticated users to cause a denial of service (device reload) via malformed IPsec packets, aka Bug ID CSCui79745.
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Analysis
by VulDB Data Team • 12/17/2024
Cisco IOS devices are vulnerable to a denial of service condition triggered by malformed IPsec packets, representing a critical security flaw that can disrupt network operations. This vulnerability affects multiple Cisco IOS software versions and impacts devices configured with IPsec VPN functionality. The flaw specifically manifests when the IOS processing engine encounters malformed IPsec packets that contain unexpected or invalid packet structures. The vulnerability is categorized under CWE-129 as an input validation issue where the system fails to properly validate incoming packet data before processing. Attackers with authenticated access to the network can exploit this weakness to force device reloads, effectively causing service disruption.
The technical implementation of this vulnerability involves the IOS IPsec processing module failing to properly handle malformed packet headers or payload structures within IPsec tunnels. When such malformed packets are received and processed by the vulnerable IOS software, the system experiences an unexpected state that leads to a device restart. The attack requires only authenticated network access, making it particularly dangerous as it can be executed by insiders or compromised accounts with legitimate network credentials. The exploitation process typically involves crafting specific IPsec packets that trigger buffer overflows or state machine inconsistencies within the IOS processing engine, ultimately leading to the system crash and subsequent reload.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise network availability and business continuity. Organizations relying on Cisco IOS devices for critical network infrastructure may face significant downtime when this vulnerability is exploited, especially in environments where IPsec VPNs are extensively used for remote access or site-to-site connectivity. The vulnerability affects various Cisco IOS platforms including routers and switches running affected software versions, making it a widespread concern across enterprise networks. Network administrators may experience unexpected device reboots during peak usage periods, leading to service degradation or complete network outages that can affect multiple users and applications simultaneously.
Mitigation strategies for this vulnerability should focus on implementing immediate software patches provided by Cisco, which address the specific packet validation flaws in the IPsec processing module. Network segmentation and access control measures can help limit the potential impact by restricting unauthorized access to network devices. Monitoring network traffic for malformed IPsec packets can serve as an early detection mechanism, allowing administrators to identify potential exploitation attempts. Organizations should also implement network access controls to ensure that only authorized users can establish IPsec connections, reducing the attack surface. The vulnerability aligns with ATT&CK technique T1499 which covers network denial of service attacks, and represents a significant risk for organizations that depend on stable network infrastructure for business operations. Regular security assessments and vulnerability management processes should include verification of IOS software versions to ensure all devices are running patched firmware that addresses this specific vulnerability.