Vulnerability · CVE-2026-20007
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacke…
Published Mar 4, 2026 · catalog updated Aug 20, 2026 · secure firewall threat defense
Check if you run it
No confirmed exploitation is on record for CVE-2026-20007. EPSS is 0.24%. Act only if a listed version of secure firewall threat defense is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium5.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.24%
- Remediation
- Advisory link
- Affected products
- cpe cisco/secure firewall threat defense
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vulnerability is due to a logic error in the integration of the Snort Engine rules with Cisco Secure FTD Software that could allow different Snort rules to be hit when deep inspection of the packet is performed for the inner and outer connections. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device that would hit configured Snort rules. A successful exploit could allow the attacker to send traffic to a network where it should have been denied.
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.
- cpe cisco/secure firewall threat defense6.4.0
- cpe cisco/secure firewall threat defense6.4.0.1
- cpe cisco/secure firewall threat defense6.4.0.2
- cpe cisco/secure firewall threat defense6.4.0.3
- cpe cisco/secure firewall threat defense6.4.0.4
- cpe cisco/secure firewall threat defense6.4.0.5
- cpe cisco/secure firewall threat defense6.4.0.6
- cpe cisco/secure firewall threat defense6.4.0.7
How to fix CVE-2026-20007
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
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-2026-20007. EPSS is 0.24%. Act only if a listed version of secure firewall threat defense is installed.
Which versions are affected?
Compare what you have installed with cisco/secure firewall threat defense 6.4.0; cisco/secure firewall threat defense 6.4.0.1; cisco/secure firewall threat defense 6.4.0.2; cisco/secure firewall threat defense 6.4.0.3. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-284: Improper Access Control. EPSS 0.24%. 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.
Mar 4, 2026 · NIST NVD
Detected
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vulnerability is due to a logic error in the integration of the Snort Engine rules with Cisco Secure FTD Software that could al
Aug 20, 2026 · NIST NVD
Updated
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vulnerability is due to a logic error in the integration of the Snort Engine rules with Cisco Secure FTD Software that could al
Sources
- CVE.orgVulnerability recordCVE-2026-20007
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-20007
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2026-20007
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vuln
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.