Vulnerabilities

Vulnerability · CVE-2025-20136

A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software an

Published Aug 14, 2025 · catalog updated Aug 14, 2025 · Cisco Cisco Firepower Threat Defense Software

Last checked Oct 27, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2025-20136. EPSS is 0.64%. Act only if a listed version of Cisco Cisco Firepower Threat Defense Software is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
High8.6
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.64%
Remediation
Advisory link
Affected products
vendor Cisco Cisco Firepower Threat Defense Software 7.2.8.1

A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall 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 an infinite loop condition that occurs when a Cisco Secure ASA or Cisco Secure FTD device processes DNS packets with DNS inspection enabled and the device is configured for NAT44, NAT64, or NAT46

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor Cisco Cisco Firepower Threat Defense Software 7.2.8.17.2.8.1

How to fix CVE-2025-20136

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2025-20136. EPSS is 0.64%. Act only if a listed version of Cisco Cisco Firepower Threat Defense Software is installed.

Which versions are affected?

Compare what you have installed with Cisco Cisco Firepower Threat Defense Software 7.2.8.1 7.2.8.1. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.64%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Technology hubs

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 14, 2025 · EUVD

    Detected

    A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall 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 du

  2. Aug 14, 2025 · EUVD

    Updated

    A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall 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 du

Sources

  • CVE.orgVulnerability recordCVE-2025-20136

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-20136

    30-day exploitation probability 0.64%

    first.org
  • EUVDVulnerability recordEUVD-2025-24852

    A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacke

    euvd.enisa.europa.eu

References

Freshness

Last verified in this catalog Oct 27, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • FIRST EPSSOct 24, 2026
  • CVE.orgOct 21, 2026
  • EUVDOct 20, 2026