ReviewHigh

CVE-2020-3529

Cisco Cisco Adaptive Security Appliance (ASA) Software, adaptive security appliance, secure firewall threat defense

A vulnerability in the SSL VPN negotiation process for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to inefficient direct memory access (DMA) memory management during the negotiation phase of an SSL VPN connection. An attacker could exploit this vulnerability by sending a steady stream of crafted Datagram TLS (DTLS) traffic to an affected device. A successful exploit could all...

CVSS
7.5
EPSS
1.85%
77.7% percentile
CISA KEV
Not listed
Published
2020.10.22
PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability1.85%
Technical severityCVSS 7.5

Vulnerability overview

A vulnerability in the SSL VPN negotiation process for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to inefficient direct memory access (DMA) memory management during the negotiation phase of an SSL VPN connection. An attacker could exploit this vulnerability by sending a steady stream of crafted Datagram TLS (DTLS) traffic to an affected device. A successful exploit could all...

Affected product and versions

Product
Cisco Cisco Adaptive Security Appliance (ASA) Software, adaptive security appliance, secure firewall threat defense
Affected versions
< 9.6.4.45, < 6.3.0.6, >= 6.4.0 < 6.4.0.10, >= 6.5.0 < 6.5.0.5, >= 6.6.0 < 6.6.1, >= 9.8.0 < 9.8.4.29, >= 9.9.0 < 9.9.2.80, >= 9.10.0 < 9.10.1.44, >= 9.12.0 < 9.12.4.4, >= 9.13.0 < 9.13.1.13, >= 9.14.0 < 9.14.1.30
Fixed versions
9.6.4.45, 6.3.0.6, 6.4.0.10, 6.5.0.5, 6.6.1, 9.8.4.29, 9.9.2.80, 9.10.1.44, 9.12.4.4, 9.13.1.13, 9.14.1.30

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Cisco Cisco Adaptive Security Appliance (ASA) Software, adaptive security appliance, secure firewall threat defense and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-400