CVE-2022-22178 in Junos OS
Summary
by MITRE • 01/19/2022
A Stack-based Buffer Overflow vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on MX Series and SRX series allows an unauthenticated networked attacker to cause a flowd crash and thereby a Denial of Service (DoS). Continued receipt of these specific packets will cause a sustained Denial of Service condition. This issue can be triggered by a specific Session Initiation Protocol (SIP) invite packet if the SIP ALG is enabled. Due to this, the PIC will be rebooted and all traffic that traverses the PIC will be dropped. This issue affects: Juniper Networks Junos OS 20.4 versions prior to 20.4R3-S2; 21.1 versions prior to 21.1R2-S1, 21.1R3; 21.2 versions prior to 21.2R2; 21.3 versions prior to 21.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 20.4R1.
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Analysis
by VulDB Data Team • 01/20/2022
The vulnerability CVE-2022-22178 represents a critical stack-based buffer overflow in the flow processing daemon (flowd) of Juniper Networks Junos OS affecting MX Series and SRX series devices. This flaw resides in the application layer gateway implementation specifically within the Session Initiation Protocol (SIP) ALG functionality, creating a pathway for unauthenticated remote attackers to exploit the system. The vulnerability manifests when the flowd daemon processes malformed SIP INVITE packets, leading to memory corruption that results in daemon termination and subsequent system instability.
The technical exploitation of this vulnerability leverages a specific packet structure that triggers the buffer overflow during SIP ALG processing. When the flowd daemon receives these crafted SIP INVITE packets, the stack buffer overflow occurs in the flow processing code path, causing the daemon to crash and restart. This crash propagates to the Packet Input/Output Controller (PIC) level, resulting in complete PIC reboot and immediate traffic disruption. The vulnerability's impact extends beyond simple daemon restarts as continuous receipt of these malicious packets maintains the DoS condition, effectively rendering the device non-functional until manual intervention occurs. The flaw demonstrates a classic buffer overflow pattern where insufficient input validation allows an attacker to overwrite adjacent memory locations, leading to arbitrary code execution potential and system instability.
From an operational perspective, this vulnerability presents significant risk to network infrastructure as it enables remote attackers to perform denial of service attacks without requiring authentication credentials. The attack vector through SIP ALG functionality makes it particularly dangerous in environments where VoIP services are deployed, as legitimate SIP traffic could be used to trigger the vulnerability. The cascading effect of PIC rebooting and traffic dropping creates substantial network disruption, affecting service availability and potentially impacting critical communications. The vulnerability affects multiple Junos OS versions across the 20.4, 21.1, 21.2, and 21.3 release lines, with specific patch versions provided to address the issue. This widespread impact across multiple release trains indicates the vulnerability's severity and the need for prompt remediation across affected deployments.
Security practitioners should recognize this vulnerability as mapping to CWE-121 Stack-based Buffer Overflow, which is classified under the broader category of memory safety issues in software development. The attack pattern aligns with ATT&CK technique T1499.004 for network denial of service, specifically targeting network infrastructure to disrupt service availability. The vulnerability's characteristics also relate to the broader category of privilege escalation through application-level attacks, as the unauthenticated nature allows attackers to compromise system availability without requiring elevated privileges. Organizations should implement immediate mitigations including disabling SIP ALG functionality when not required, applying the relevant Junos OS patches, and monitoring network traffic for suspicious SIP INVITE packet patterns. Network segmentation and intrusion detection systems should be configured to detect and block potential exploitation attempts, while security teams should maintain awareness of the vulnerability's impact on VoIP infrastructure and network reliability.