CVE-2018-0244
MediumCVSS 5.8Exploitation Probability (EPSS)
Elevated risk66th percentile - higher than 66% of all known CVEs
Summary
A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass a configured file action policy to drop the SMB protocol if a malware file is detected. The issue is due to how SMB handles a case where a large file transfer fails. An attacker could send a crafted SMB file transfer request through the device, allowing an SMB file containing malware to pass.
Risk Assessment
Bypassing file action policies could allow malware to enter the network, potentially leading to infections and security breaches.
Recommendation
It is recommended to update Firepower software to version 6.2.3 or later and review file policy configurations.
Original NVD description (English source)
A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass a configured file action policy to drop the Server Message Block (SMB) protocol if a malware file is detected. The vulnerability is due to how the SMB protocol handles a case in which a large file transfer fails. This case occurs when some pieces of the file are successfully transferred to the remote endpoint, but ultimately the file transfer fails and is reset. An attacker could exploit this vulnerability by sending a crafted SMB file transfer request through the targeted device. An exploit could allow the attacker to pass an SMB file that contains malware, which the device is configured to block. This vulnerability affects Cisco Firepower System Software when one or more file action policies are configured, on software releases prior to 6.2.3. Cisco Bug IDs: CSCvc20141.