CVE-2018-15399

Cisco Adaptive Security Appliance TCP Syslog Denial of Service Vulnerability

Description

A vulnerability in the TCP syslog module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust the 1550-byte buffers on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing boundary check in an internal function. An attacker could exploit this vulnerability by establishing a man-in-the-middle position between an affected device and its configured TCP syslog server and then maliciously modifying the TCP header in segments that are sent from the syslog server to the affected device. A successful exploit could allow the attacker to exhaust buffer on the affected device and cause all TCP-based features to stop functioning, resulting in a DoS condition. The affected TCP-based features include AnyConnect SSL VPN, clientless SSL VPN, and management connections such as Secure Shell (SSH), Telnet, and HTTPS.

Categories

6.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.45%
Vendor Advisory cisco.com
Affected: Cisco Cisco Adaptive Security Appliance (ASA) Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2018-15399?
CVE-2018-15399 has been scored as a medium severity vulnerability.
How to fix CVE-2018-15399?
To fix CVE-2018-15399, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-15399 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-15399 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-15399?
CVE-2018-15399 affects Cisco Cisco Adaptive Security Appliance (ASA) Software.
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