# Cisco Firepower Threat Defense vulnerabilities Source: https://junglewise.ai/threats/technologies/firepower-threat-defense Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats Updated: 11 November 2026, 03:07 UTC. Rebuilt every hour. Data: https://junglewise.ai/threats/technologies/firepower-threat-defense.json License: CC BY 4.0 with a link back Junglewise Threat Intelligence has tracked 33 vulnerabilities in Cisco Firepower Threat Defense: 0 in the last 7 days and 16 in the last 90 days, 4 of them critical and 3 exploited in the wild. The most recent, CVE-2026-76489, was published on 21 October 2026. 11 vulnerabilities in the last four weeks, up 120% on the four before (5). 1 critical against 0. ## Counts - Last 7 days: 0 - Last 30 days: 11 - Last 90 days: 16 - All time: 33 (4 critical, 3 exploited in the wild) ## About Cisco Firepower Threat Defense Cisco security platform that provides threat defense, intrusion prevention, and firewall capabilities. ## Latest Cisco Firepower Threat Defense vulnerabilities - [CVE-2026-76489: Cisco Snort 3 memory management denial of service](https://junglewise.ai/threats/cve-2026-76489-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-76445: Cisco Snort 3 Detection Engine denial of service in GTP codec](https://junglewise.ai/threats/cve-2026-76445-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.3, published 21 Oct 2026) - [CVE-2026-20356: Cisco Snort 3 uncontrolled resource consumption](https://junglewise.ai/threats/cve-2026-20356-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.5, published 21 Oct 2026) - [CVE-2026-20291: Cisco Snort 3 improper privilege management](https://junglewise.ai/threats/cve-2026-20291-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.8, published 21 Oct 2026) - [CVE-2026-20236: Cisco Snort 3 incorrect calculation vulnerability](https://junglewise.ai/threats/cve-2026-20236-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.5, published 21 Oct 2026) - [CVE-2026-20221: Cisco multiple products Snort 3 GRE tunnel denial of service](https://junglewise.ai/threats/cve-2026-20221-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-20218: Cisco Snort 3 VBA decompression buffer overflow denial of service](https://junglewise.ai/threats/cve-2026-20218-a-vulnerability-in-the-snort-3-visual-basic-for-applications-vba) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-20197: Cisco Snort 3 Teredo detection engine denial of service](https://junglewise.ai/threats/cve-2026-20197-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-20043: Cisco Snort 3 out-of-bounds write](https://junglewise.ai/threats/cve-2026-20043-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (critical, CVSS 9, published 21 Oct 2026) - [CVE-2026-20019: Cisco Snort 3 NetFlow Detection Engine denial of service](https://junglewise.ai/threats/cve-2026-20019-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-20011: Cisco multiple products SMTP MIME parsing denial of service in Snort 3](https://junglewise.ai/threats/cve-2026-20011-multiple-cisco-products-are-affected-by-a-vulnerability-in-the) (medium, CVSS 5.8, published 21 Oct 2026) - [CVE-2026-20336: Cisco Secure Firewall software resource lifecycle vulnerability](https://junglewise.ai/threats/cve-2026-20336-cisco-secure-firewall-software-resource-lifecycle-vulnerability) (high, CVSS 8.8, published 16 Sep 2026) - [CVE-2026-20323: Cisco Secure FMC and FTD sftunnel authentication bypass](https://junglewise.ai/threats/cve-2026-20323-cisco-secure-fmc-and-ftd-sftunnel-authentication-bypass) (high, CVSS 8.3, published 16 Sep 2026) - [CVE-2026-20295: Cisco Secure FMC and FTD memory exhaustion in sftunnel](https://junglewise.ai/threats/cve-2026-20295-cisco-secure-fmc-and-ftd-memory-exhaustion-in-sftunnel) (high, CVSS 8.6, published 16 Sep 2026) - [CVE-2026-20290: Cisco Secure Firewall Threat Defense SSL/TLS denial of service in Snort 2](https://junglewise.ai/threats/cve-2026-20290-cisco-secure-firewall-threat-defense-ssl-tls-denial-of-service-in) (medium, CVSS 5.8, published 16 Sep 2026) - [CVE-2026-20120: Cisco Secure Firewall ASA/FTD access control bypass in OGS](https://junglewise.ai/threats/cve-2026-20120-cisco-secure-firewall-asa-ftd-access-control-bypass-in-ogs) (medium, CVSS 5.8, published 16 Sep 2026) - [CVE-2026-20064: Cisco Secure Firewall Threat Defense authenticated DoS via CLI input validation](https://junglewise.ai/threats/cve-2026-20064-cisco-secure-firewall-threat-defense-authenticated-dos-via-cli) (medium, CVSS 6.5, published 4 Mar 2026) - [CVE-2026-20016: Cisco Secure Firewall ASA and FTD command injection in FXOS CLI](https://junglewise.ai/threats/cve-2026-20016-cisco-secure-firewall-asa-and-ftd-command-injection-in-fxos-cli) (medium, CVSS 6, published 4 Mar 2026) - [CVE-2026-20068: Cisco Snort 3 detection engine denial of service](https://junglewise.ai/threats/cve-2026-20068-cisco-snort-3-detection-engine-denial-of-service) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20066: Cisco Snort 3 Detection Engine denial of service in HTTP JavaScript normalization](https://junglewise.ai/threats/cve-2026-20066-cisco-snort-3-detection-engine-denial-of-service-in-http) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20065: Cisco Snort 3 Detection Engine denial of service](https://junglewise.ai/threats/cve-2026-20065-cisco-snort-3-detection-engine-denial-of-service) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20057: Cisco Snort 3 VBA decompression denial of service](https://junglewise.ai/threats/cve-2026-20057-cisco-snort-3-vba-decompression-denial-of-service) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20053: Cisco Snort 3 VBA decompression denial of service](https://junglewise.ai/threats/cve-2026-20053-cisco-snort-3-vba-decompression-denial-of-service) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20052: Cisco Secure Firewall Threat Defense Snort 3 memory management denial of service](https://junglewise.ai/threats/cve-2026-20052-cisco-secure-firewall-threat-defense-snort-3-memory-management) (medium, CVSS 5.8, published 4 Mar 2026) - [CVE-2026-20050: Cisco Secure Firewall Threat Defense SSL decryption denial of service](https://junglewise.ai/threats/cve-2026-20050-cisco-secure-firewall-threat-defense-ssl-decryption-denial-of) (medium, CVSS 6.8, published 4 Mar 2026) ## Most severe Cisco Firepower Threat Defense vulnerabilities - [CVE-2025-20333: Cisco ASA and FTD buffer overflow in VPN web server](https://junglewise.ai/threats/cve-2025-20333-cisco-asa-and-ftd-buffer-overflow-in-vpn-web-server) (critical, exploited in the wild, CVSS 9.9, published 25 Sep 2025) - [CVE-2023-20269: Cisco Adaptive Security Appliance and Firepower Threat Defense Unauthorized Access Vulnerability](https://junglewise.ai/threats/cve-2023-20269-cisco-adaptive-security-appliance-and-firepower-threat-defense) (critical, exploited in the wild, CVSS 9.1, published 13 Sep 2023) - [CVE-2025-20362: Cisco Secure Firewall ASA and FTD missing authorization in VPN web server](https://junglewise.ai/threats/cve-2025-20362-cisco-secure-firewall-asa-and-ftd-missing-authorization-in-vpn) (critical, exploited in the wild, CVSS 6.5, published 25 Sep 2025) - [CVE-2026-20043: Cisco Snort 3 out-of-bounds write](https://junglewise.ai/threats/cve-2026-20043-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (critical, CVSS 9, published 21 Oct 2026) - [CVE-2026-20336: Cisco Secure Firewall software resource lifecycle vulnerability](https://junglewise.ai/threats/cve-2026-20336-cisco-secure-firewall-software-resource-lifecycle-vulnerability) (high, CVSS 8.8, published 16 Sep 2026) - [CVE-2026-20295: Cisco Secure FMC and FTD memory exhaustion in sftunnel](https://junglewise.ai/threats/cve-2026-20295-cisco-secure-fmc-and-ftd-memory-exhaustion-in-sftunnel) (high, CVSS 8.6, published 16 Sep 2026) - [CVE-2026-20323: Cisco Secure FMC and FTD sftunnel authentication bypass](https://junglewise.ai/threats/cve-2026-20323-cisco-secure-fmc-and-ftd-sftunnel-authentication-bypass) (high, CVSS 8.3, published 16 Sep 2026) - [CVE-2026-20291: Cisco Snort 3 improper privilege management](https://junglewise.ai/threats/cve-2026-20291-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.8, published 21 Oct 2026) - [CVE-2026-20356: Cisco Snort 3 uncontrolled resource consumption](https://junglewise.ai/threats/cve-2026-20356-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.5, published 21 Oct 2026) - [CVE-2026-20236: Cisco Snort 3 incorrect calculation vulnerability](https://junglewise.ai/threats/cve-2026-20236-as-part-of-cisco-s-ongoing-commitment-to-proactive-security-and) (high, CVSS 7.5, published 21 Oct 2026) ## Vulnerabilities per week 11 vulnerabilities in the last four weeks, up 120% on the four before (5). 1 critical against 0. | Week of | Vulns | Critical | Exploited | | --- | --- | --- | --- | | 17 Aug 2026 | 0 | 0 | 0 | | 24 Aug 2026 | 0 | 0 | 0 | | 31 Aug 2026 | 0 | 0 | 0 | | 7 Sep 2026 | 0 | 0 | 0 | | 14 Sep 2026 | 5 | 0 | 0 | | 21 Sep 2026 | 0 | 0 | 0 | | 28 Sep 2026 | 0 | 0 | 0 | | 5 Oct 2026 | 0 | 0 | 0 | | 12 Oct 2026 | 0 | 0 | 0 | | 19 Oct 2026 | 11 | 1 | 0 | | 26 Oct 2026 | 0 | 0 | 0 | | 2 Nov 2026 | 0 | 0 | 0 | | 9 Nov 2026 | 0 | 0 | 0 | ## Other Cisco technologies - [Cisco IOS](https://junglewise.ai/threats/technologies/ios): 70 vulnerabilities - [Cisco Identity Services Engine](https://junglewise.ai/threats/technologies/identity-services-engine): 58 vulnerabilities - [Cisco IOS XE](https://junglewise.ai/threats/technologies/ios-xe): 57 vulnerabilities - [Cisco Firepower Threat Defense Software](https://junglewise.ai/threats/technologies/firepower-threat-defense-software): 33 vulnerabilities - [Cisco IOS XR](https://junglewise.ai/threats/technologies/ios-xr): 31 vulnerabilities - [Cisco IOS XE Software](https://junglewise.ai/threats/technologies/ios-xe-software): 28 vulnerabilities - [Cisco Adaptive Security Appliance Software](https://junglewise.ai/threats/technologies/secure-firewall-asa-software): 23 vulnerabilities - [Cisco Snort 3](https://junglewise.ai/threats/technologies/snort-3): 20 vulnerabilities - [Cisco Ios Software](https://junglewise.ai/threats/technologies/ios-software): 19 vulnerabilities - [Cisco ISE Passive Identity Connector](https://junglewise.ai/threats/technologies/ise-passive-identity-connector): 19 vulnerabilities - [Cisco Secure Firewall Management Center](https://junglewise.ai/threats/technologies/secure-firewall-management-center): 16 vulnerabilities - [Cisco Unity Connection](https://junglewise.ai/threats/technologies/unity-connection): 16 vulnerabilities ## Sources NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "Cisco Firepower Threat Defense vulnerabilities", https://junglewise.ai/threats/technologies/firepower-threat-defense, 11 November 2026.