Cisco Secure Firewall Threat Defense Software Snort Deep Inspection Bypass Vulnerability
Published Mar 4, 2026
5.8
MEDIUMCVSS 3.1
EPSS 0.23%
Description
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.
Affected products
-
- Version 6.4.0StatusaffectedConstraints-
- Version 6.4.0.1StatusaffectedConstraints-
- Version 6.4.0.10StatusaffectedConstraints-
- Version 6.4.0.11StatusaffectedConstraints-
- Version 6.4.0.12StatusaffectedConstraints-
- Version 6.4.0.13StatusaffectedConstraints-
- Version 6.4.0.14StatusaffectedConstraints-
- Version 6.4.0.15StatusaffectedConstraints-
- Version 6.4.0.16StatusaffectedConstraints-
- Version 6.4.0.17StatusaffectedConstraints-
- Version 6.4.0.18StatusaffectedConstraints-
- Version 6.4.0.2StatusaffectedConstraints-
- Version 6.4.0.3StatusaffectedConstraints-
- Version 6.4.0.4StatusaffectedConstraints-
- Version 6.4.0.5StatusaffectedConstraints-
- Version 6.4.0.6StatusaffectedConstraints-
- Version 6.4.0.7StatusaffectedConstraints-
- Version 6.4.0.8StatusaffectedConstraints-
- Version 6.4.0.9StatusaffectedConstraints-
- Version 7.0.0StatusaffectedConstraints-
- Version 7.0.0.1StatusaffectedConstraints-
- Version 7.0.1StatusaffectedConstraints-
- Version 7.0.1.1StatusaffectedConstraints-
- Version 7.0.2StatusaffectedConstraints-
- Version 7.0.2.1StatusaffectedConstraints-
- Version 7.0.3StatusaffectedConstraints-
- Version 7.0.4StatusaffectedConstraints-
- Version 7.0.5StatusaffectedConstraints-
- Version 7.0.6StatusaffectedConstraints-
- Version 7.0.6.1StatusaffectedConstraints-
- Version 7.0.6.2StatusaffectedConstraints-
- Version 7.0.6.3StatusaffectedConstraints-
- Version 7.0.7StatusaffectedConstraints-
- Version 7.0.8StatusaffectedConstraints-
- Version 7.0.8.1StatusaffectedConstraints-
- Version 7.1.0StatusaffectedConstraints-
- Version 7.1.0.1StatusaffectedConstraints-
- Version 7.1.0.2StatusaffectedConstraints-
- Version 7.1.0.3StatusaffectedConstraints-
- Version 7.2.0StatusaffectedConstraints-
- Version 7.2.0.1StatusaffectedConstraints-
- Version 7.2.1StatusaffectedConstraints-
- Version 7.2.10StatusaffectedConstraints-
- Version 7.2.10.2StatusaffectedConstraints-
- Version 7.2.2StatusaffectedConstraints-
- Version 7.2.3StatusaffectedConstraints-
- Version 7.2.4StatusaffectedConstraints-
- Version 7.2.4.1StatusaffectedConstraints-
- Version 7.2.5StatusaffectedConstraints-
- Version 7.2.5.1StatusaffectedConstraints-
- Version 7.2.5.2StatusaffectedConstraints-
- Version 7.2.6StatusaffectedConstraints-
- Version 7.2.7StatusaffectedConstraints-
- Version 7.2.8StatusaffectedConstraints-
- Version 7.2.8.1StatusaffectedConstraints-
- Version 7.2.9StatusaffectedConstraints-
- Version 7.3.0StatusaffectedConstraints-
- Version 7.3.1StatusaffectedConstraints-
- Version 7.3.1.1StatusaffectedConstraints-
- Version 7.3.1.2StatusaffectedConstraints-
- Version 7.4.0StatusaffectedConstraints-
- Version 7.4.1StatusaffectedConstraints-
- Version 7.4.1.1StatusaffectedConstraints-
- Version 7.4.2StatusaffectedConstraints-
- Version 7.4.2.1StatusaffectedConstraints-
- Version 7.4.2.2StatusaffectedConstraints-
- Version 7.4.2.3StatusaffectedConstraints-
- Version 7.4.2.4StatusaffectedConstraints-
- Version 7.6.0StatusaffectedConstraints-
- Version 7.6.1StatusaffectedConstraints-
- Version 7.6.2StatusaffectedConstraints-
- Version 7.6.2.1StatusaffectedConstraints-
- Version 7.7.0StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | n/a |
|
- 6.4.0
- 6.4.0.1
- 6.4.0.2
- 6.4.0.3
- 6.4.0.4
- 6.4.0.5
- 6.4.0.6
- 6.4.0.7
- 6.4.0.8
- 6.4.0.9
- 6.4.0.10
- 6.4.0.11
- 6.4.0.12
- 6.4.0.13
- 6.4.0.14
- 6.4.0.15
- 6.4.0.16
- 6.4.0.17
- 6.4.0.18
- 7.0.0
- 7.0.0.1
- 7.0.1
- 7.0.1.1
- 7.0.2
- 7.0.2.1
- 7.0.3
- 7.0.4
- 7.0.5
- 7.0.6
- 7.0.6.1
- 7.0.6.2
- 7.0.6.3
- 7.0.7
- 7.0.8
- 7.0.8.1
- 7.1.0
- 7.1.0.1
- 7.1.0.2
- 7.1.0.3
- 7.2.0
- 7.2.0.1
- 7.2.1
- 7.2.2
- 7.2.3
- 7.2.4
- 7.2.4.1
- 7.2.5
- 7.2.5.1
- 7.2.5.2
- 7.2.6
- 7.2.7
- 7.2.8
- 7.2.8.1
- 7.2.9
- 7.2.10
- 7.2.10.2
- 7.3.0
- 7.3.1
- 7.3.1.1
- 7.3.1.2
- 7.4.0
- 7.4.1
- 7.4.1.1
- 7.4.2
- 7.4.2.1
- 7.4.2.2
- 7.4.2.3
- 7.4.2.4
- 7.6.0
- 7.6.1
- 7.6.2
- 7.6.2.1
- 7.7.0
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Mar 4, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Mar–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.23% (0.00232) | 12.73th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.25% (0.00247) | 15.74th | v5 (v2026.06.15) |
| Mar 5, 2026 | 0.02% (0.00023) | 5.82th | v4 (v2025.03.14) |
References (1)
Change history (0)
No recorded changes yet.