CVE-2022-25291 in Firebox
Summary
by MITRE • 02/24/2022
An integer overflow in WatchGuard Firebox and XTM appliances allows an authenticated remote attacker to trigger a heap-based buffer overflow and potentially execute arbitrary code by initiating a firmware update with a malicious upgrade image. This vulnerability impacts Fireware OS before 12.7.2_U2, 12.x before 12.1.3_U8, and 12.2.x through 12.5.x before 12.5.9_U2.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 02/26/2022
This vulnerability represents a critical integer overflow flaw within the firmware update mechanism of WatchGuard Firebox and XTM appliances that operates at the system level. The vulnerability stems from improper input validation during firmware image processing, where an authenticated remote attacker can manipulate the upgrade image to cause integer overflow conditions. When the system processes a malicious firmware image, the overflow corrupts heap memory structures leading to a heap-based buffer overflow condition. This type of vulnerability falls under the CWE-190 category for integer overflow and aligns with ATT&CK technique T1059.3.005 for execution through command and scripting interpreter, as the attacker could potentially execute arbitrary code through the compromised system memory.
The technical implementation of this flaw occurs during the firmware update process where the appliance's operating system fails to properly validate the size parameters of incoming firmware images. When an attacker crafts a malicious upgrade image with manipulated size fields, the system's integer arithmetic operations overflow beyond the maximum representable value, creating a memory corruption scenario that can be exploited to overwrite adjacent heap memory. This vulnerability specifically affects Fireware OS versions prior to 12.7.2_U2, 12.1.3_U8, and 12.5.9_U2, indicating that the fix likely addressed the integer overflow handling in the firmware update parser and heap management routines. The impact extends beyond simple privilege escalation as the heap corruption can potentially lead to complete system compromise and arbitrary code execution.
From an operational perspective, this vulnerability presents a significant risk to network security infrastructure as it requires only authentication credentials to exploit, making it particularly dangerous in environments where administrative access might be compromised. The remote nature of the attack means that an attacker could potentially exploit this vulnerability from outside the network perimeter, provided they have valid credentials to access the appliance's management interface. The attack vector involves initiating a firmware update process through the web-based management interface or API, making it accessible through standard network protocols. Organizations using affected WatchGuard appliances face potential unauthorized access to their network security devices, which could lead to complete network compromise, data exfiltration, and disruption of security services. The vulnerability's classification under CWE-190 and its exploitation pattern align with ATT&CK tactic TA0002 for execution and TA0006 for credential access, highlighting the multi-faceted attack surface this vulnerability presents.
Mitigation strategies for this vulnerability should include immediate deployment of the vendor-provided security patches for Fireware OS versions mentioned in the advisory. Organizations should also implement network segmentation to limit access to management interfaces and enforce strict access controls using multi-factor authentication. Monitoring for unusual firmware update activities and implementing network-based intrusion detection systems can help identify potential exploitation attempts. Regular security assessments of network infrastructure devices should include vulnerability scanning for similar integer overflow conditions in other network appliances. The remediation process should involve verifying the integrity of firmware images through cryptographic signatures and ensuring that only trusted firmware sources are used for updates. Additionally, organizations should maintain detailed audit logs of firmware update activities and establish incident response procedures for potential exploitation attempts, as the vulnerability's exploitation could lead to complete system compromise and require full system restoration.