CVE-2024-20353: high-severity vulnerability in Cisco Adaptive Security Appliance (ASA) Software
Published · Updated
93Vexday Risk Score
Prioritize patching. It under exploitation confirmed by CISA and has a public proof of concept.
ssvc Actcvss 8.6epss 71%
from disclosure to weapon
Published on NVDApr 24
CISA KEVApr 24
exploitation probability
71%top 1% of all CVEs
observed exploitation
yesCISA + VulnCheck
1 public exploit(s)
Action required by CISAfederal deadline: 2024-05-01
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
In short
A flaw in Cisco ASA and FTD firewalls allows attackers to crash the device by sending a specially crafted HTTP request to the web server, causing it to restart and temporarily stop protecting the network.
Technical detail
The vulnerability stems from incomplete error checking in HTTP header parsing within the management and VPN web servers of Cisco ASA and FTD. An unauthenticated remote attacker can exploit this by sending a malformed HTTP request, triggering an unhandled exception that causes unexpected device reload, resulting in denial of service.
Summary generated and translated by AI from the official description.
A vulnerability in the management and VPN web servers for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.
This vulnerability is due to incomplete error checking when parsing an HTTP header. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted web server on a device. A successful exploit could allow the attacker to cause a DoS condition when the device reloads.