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Mallory
Medium

Snort deep packet inspection rule bypass in Cisco Secure Firewall Threat Defense (FTD)

IdentifiersCVE-2026-20007CWE-693

A vulnerability in the Snort 2 and Snort 3 deep packet inspection integration within Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated remote attacker to bypass configured Snort rules, permitting traffic that should have been dropped. The issue is described as a logic error in how Snort Engine rules are applied during deep inspection such that different Snort rules may be matched for the inner versus outer connections, enabling crafted traffic to evade intended rule enforcement.

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Impact

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Successful exploitation allows bypass of configured Snort inspection/rules on the targeted FTD device, resulting in unauthorized/undesired traffic being allowed onto the protected network that policy should have denied (security control evasion).

Mitigation

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Information currently not available in the provided content (no workaround/mitigation guidance included).

Remediation

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PUBLIC EXPLOITS

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

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Threat actor evidence

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Associated malware

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Detection signatures

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Vendor-by-vendor mapping

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Social activity1

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