Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2020-3565)
Summary
Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2020-3565). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A vulnerability in the TCP Intercept functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Access Control Policies (including Geolocation) and Service Polices on an affected system. The vulnerability exists because TCP Intercept is invoked when the embryonic connection limit is reached, which can cause the underlying detection engine to process the packet incorrectly. An attacker could exploit this vulnerability by sending a crafted stream of traffic that matches a policy on which TCP Intercept is configured. A successful exploit could allow the attacker to match on an incorrect policy, which could allow the traffic to be forwarded when it should be dropped. In addition, the traffic could incorrectly be dropped.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2020-3565 has been found in Cisco Firepower Threat Defense (FTD) Software.
Risk of unauthorized operations or information disclosure. CVSS score: 5.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Cisco Firepower Threat Defense (FTD) Software CVE-2020-3565" on the vendor's site.
CVE-2020-3565 (Cisco Firepower Threat Defense (FTD) Software) — CWE-284 / CVSS v3 5.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-284) exists in Cisco Firepower Threat Defense (FTD) Software.
Check the vendor advisory for the affected versions of Cisco Firepower Threat Defense (FTD) Software.
Severity: Medium (CVSS 5.8/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Cisco Firepower Threat Defense (FTD) Software を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web tools.cisco.com
- web nvd.nist.gov
- web github.com