CWE
755 20
Advisory Published
CVE Published
CVE Published
Updated

CVE-2019-1691: Cisco Firepower Threat Defense Software SSL or TLS Denial of Service Vulnerability

First published: Wed Feb 20 2019(Updated: )

A vulnerability in the detection engine of Cisco Firepower Threat Defense Software could allow an unauthenticated, remote attacker to cause the unexpected restart of the SNORT detection engine, resulting in a denial of service (DoS) condition. The vulnerability is due to the incomplete error handling of the SSL or TLS packet header during the connection establishment. An attacker could exploit this vulnerability by sending a crafted SSL or TLS packet during the connection handshake. An exploit could allow the attacker to cause the SNORT detection engine to unexpectedly restart, resulting in a partial DoS condition while the detection engine restarts. Versions prior to 6.2.3.4 are affected.

Credit: ykramarz@cisco.com ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Firepower Threat Defense<6.2.3.4
<6.2.3.4

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Frequently Asked Questions

  • What is the severity of CVE-2019-1691?

    CVE-2019-1691 has a high severity rating due to its potential to cause a denial of service.

  • How do I fix CVE-2019-1691?

    To mitigate CVE-2019-1691, upgrade Cisco Firepower Threat Defense Software to the latest version beyond 6.2.3.4.

  • What causes the vulnerability in CVE-2019-1691?

    CVE-2019-1691 is caused by an issue in the detection engine of Cisco Firepower Threat Defense Software.

  • Who is affected by CVE-2019-1691?

    CVE-2019-1691 affects users of Cisco Firepower Threat Defense Software versions below 6.2.3.4.

  • What are the risks associated with CVE-2019-1691?

    The main risk associated with CVE-2019-1691 is a denial of service condition due to the unexpected restart of the SNORT detection engine.

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