Secure Firewall ASA and FTD
CVE-2023-20083: A vulnerability in ICMPv6 inspection when configured with the Snort 2 detection engine for Cisco Firepower…
A vulnerability in ICMPv6 inspection when configured with the Snort 2 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the CPU of an affected device to spike to 100 percent, which could stop all traffic processing and result in a denial of service (DoS) condition.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.2 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.6 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.4 | See the advisory |
| Cisco Firepower Threat Defense Software 6.7 | See the advisory |
| Cisco Firepower Threat Defense Software 6.7 | See the advisory |
| Cisco Firepower Threat Defense Software 6.7 | See the advisory |
| Cisco Firepower Threat Defense Software 6.7 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.0 | See the advisory |
| Cisco Firepower Threat Defense Software 7.1 | See the advisory |
| Cisco Firepower Threat Defense Software 7.1 | See the advisory |
| Cisco Firepower Threat Defense Software 7.1 | See the advisory |
| Cisco Firepower Threat Defense Software 7.1 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in ICMPv6 inspection when configured with the Snort 2 detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the CPU of an affected device to spike to 100 percent, which could stop all traffic processing and result in a denial of service (DoS) condition. FTD management traffic is not affected by this vulnerability. This vulnerability is due to improper error checking when parsing fields within the ICMPv6 header. An attacker could exploit this vulnerability by sending a crafted ICMPv6 packet through an affected device. A successful exploit could allow the attacker to cause the device to exhaust CPU resources and stop processing traffic, resulting in a DoS condition. Note: To recover from the DoS condition, the Snort 2 Detection Engine or the Cisco FTD device may need to be restarted.
Exploitation
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.