Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2023-20177)
Summary
Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2023-20177). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A vulnerability in the SSL file policy implementation of Cisco Firepower Threat Defense (FTD) Software that occurs when the SSL/TLS connection is configured with a URL Category and the Snort 3 detection engine could allow an unauthenticated, remote attacker to cause the Snort 3 detection engine to unexpectedly restart. This vulnerability exists because a logic error occurs when a Snort 3 detection engine inspects an SSL/TLS connection that has either a URL Category configured on the SSL file policy or a URL Category configured on an access control policy with TLS server identity discovery enabled. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a crafted SSL/TLS connection through an affected device. A successful exploit could allow the attacker to trigger an unexpected reload of the Snort 3 detection engine, resulting in either a bypass or denial of service (DoS) condition, depending on device configuration. The Snort 3 detection engine will restart automatically. No manual intervention is required.
Source: NIST National Vulnerability Database NVD
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-2023-20177 has been found in Cisco Firepower Threat Defense (FTD) Software.
Risk of unauthorized operations or information disclosure. CVSS score: 4.0/10.
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-2023-20177" on the vendor's site.
CVE-2023-20177 (Cisco Firepower Threat Defense (FTD) Software) — CWE-244 / CVSS v3 4.0
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-244) 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 4.0/10). 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
- patch sec.cloudapps.cisco.com