A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol parser of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies. The vulnerability is due to improper parsing of specific attributes in a TLS packet header. An attacker could exploit this vulnerability by sending malicious TLS messages to the affected system. A successful exploit could allow the attacker to bypass the configured policies for the system, which could allow traffic to flow through without being inspected.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-1833
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-ftd-ssltls-bypass
• http://www.securityfocus.com/bid/108338