CVE-2022-22201 in Junos OS
Summary
by MITRE • 10/18/2022
An Improper Validation of Specified Index, Position, or Offset in Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated network-based attacker to cause a Denial of Service (DoS). On SRX5000 Series with SPC3, SRX4000 Series, and vSRX, when PowerMode IPsec is configured and a malformed ESP packet matching an established IPsec tunnel is received the PFE crashes. This issue affects Juniper Networks Junos OS on SRX5000 Series with SPC3, SRX4000 Series, and vSRX: All versions prior to 19.4R2-S6, 19.4R3-S7; 20.1 versions prior to 20.1R3-S3; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S3; 20.4 versions prior to 20.4R3-S2; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R3; 21.3 versions prior to 21.3R1-S2, 21.3R2.
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Analysis
by VulDB Data Team • 10/18/2022
The vulnerability described in CVE-2022-22201 represents a critical flaw in the Packet Forwarding Engine of Juniper Networks Junos OS that falls under the category of improper validation of specified index, position, or offset input. This weakness exists within the network security device firmware and specifically targets the processing of IPsec packets in certain hardware platforms. The vulnerability manifests when the system receives malformed Encapsulating Security Payload (ESP) packets that match established IPsec tunnels, creating a scenario where the Packet Forwarding Engine cannot properly validate input parameters before processing them. The flaw is particularly dangerous because it affects multiple generations of SRX series devices including SRX5000 Series with SPC3, SRX4000 Series, and virtual SRX instances, making it a widespread concern across Juniper's security portfolio.
The technical implementation of this vulnerability stems from insufficient validation mechanisms within the IPsec packet processing pipeline of the PFE component. When PowerMode IPsec is configured on affected devices, the system's handling of malformed ESP packets becomes vulnerable to exploitation. The improper validation occurs during the processing of index, position, or offset values within the packet headers, where the system fails to properly sanitize or verify the legitimacy of these parameters before using them to navigate internal data structures. This type of vulnerability aligns with CWE-129, which specifically addresses improper validation of specified index, position, or offset values, and represents a classic example of buffer overread or out-of-bounds memory access conditions. The attack vector requires only network-based access without authentication, making it particularly dangerous as an unauthenticated remote exploit that can be leveraged by attackers anywhere on the network.
The operational impact of this vulnerability extends beyond simple service disruption, creating a comprehensive denial of service scenario that can severely compromise network security infrastructure. When exploited, the malformed ESP packets cause the Packet Forwarding Engine to crash, effectively bringing down the entire security appliance or virtual instance. This DoS condition affects the core network security functions of the device, potentially leaving networks vulnerable to attack while the device remains offline. The impact is particularly severe in enterprise environments where SRX series devices serve as critical security gateways, as the compromise of these devices can disrupt network communications, disable security policies, and create windows for additional attacks. The vulnerability affects multiple software versions across different release branches, indicating that it has been present for an extended period and represents a fundamental flaw in the packet processing logic rather than a recent implementation error.
Mitigation strategies for CVE-2022-22201 should prioritize immediate firmware updates to versions that contain the necessary patches and validation fixes. Organizations should implement comprehensive patch management procedures to ensure all affected SRX series devices are updated to versions 19.4R2-S6, 19.4R3-S7, 20.1R3-S3, 20.2R3-S4, 20.3R3-S3, 20.4R3-S2, 21.1R3, 21.2R3, or later releases. Network administrators should also consider implementing temporary network segmentation or access controls to limit exposure while patches are deployed, and monitor for any signs of exploitation attempts. The vulnerability's classification under ATT&CK technique T1499.004, which covers network denial of service, indicates that defenders should enhance their monitoring capabilities to detect unusual packet patterns or device behavior that might indicate exploitation attempts. Additionally, organizations should conduct thorough testing of updated firmware in controlled environments before full deployment to ensure compatibility with existing network configurations and security policies.