--- title: "CVE-2026-20349: Cisco Secure Firewall Adaptive Security… | CubePath" description: "A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall…" language: en source: https://cubepath.com/security/cve/CVE-2026-20349 --- # CVE-2026-20349: Cisco Secure Firewall Adaptive Security… | CubePath ## Description A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient error checking when processing HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Official description from the CVE record, published by cisco. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-20349) ## Key data ### CVSS 3.1 High 8.6 Score published by cisco in the CVE record. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H | Metric | Value | What it means | | ---------------------- | ------- | ----------------------------------------------------------------------------------- | | Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. | | Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. | | Privileges required | None | No account or privileges are needed. | | User interaction | None | No action from any user is needed. | | Scope | Changed | The impact can reach other components beyond the vulnerable one. | | Confidentiality impact | None | No effect on the secrecy of data. | | Integrity impact | None | No effect on the trustworthiness of data. | | Availability impact | High | Serious or total effect on availability. | CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) . ### EPSS Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days. Score 0.01010 (1.0% probability) Percentile 63.4% Scores of Nov 10, 2026 Model v2026.06.15 ### CISA Known Exploited Vulnerabilities This CVE is listed in the CISA KEV catalog. Name in the catalog Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection Vulnerability Added to the catalog Aug 11, 2026 Federal due date Aug 14, 2026 ### CISA assessment as of Aug 11, 2026 Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA. Exploitation Recorded by CISA as active Automatable yes Technical impact partial ### Weakness (CWE) CWE catalog version 5.0. CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license. - [CWE-244](https://cwe.mitre.org/data/definitions/244.html) Improper Clearing of Heap Memory Before Release ## Affected products Products listed in the CVE record, as the CNA published them. - Cisco Secure Firewall Adaptive Security Appliance (ASA) Software - affected: 9.16.1 - affected: 9.16.1.28 - affected: 9.16.2 - affected: 9.16.2.3 - affected: 9.16.2.7 - affected: 9.16.2.11 - affected: 9.16.2.13 - affected: 9.16.2.14 - affected: 9.16.3.3 - affected: 9.16.3 - affected: 9.16.3.14 - affected: 9.18.1 - affected: 9.16.3.15 - affected: 9.18.1.3 - affected: 9.18.2 - affected: 9.16.3.19 - affected: 9.16.3.23 - affected: 9.18.2.5 - affected: 9.16.4 - affected: 9.18.2.7 - affected: 9.19.1 - affected: 9.16.4.9 - affected: 9.18.2.8 - affected: 9.16.4.14 - affected: 9.18.3 - and 107 more - Cisco Secure Firewall Threat Defense (FTD) Software - affected: 7.0.0 - affected: 7.0.0.1 - affected: 7.0.1 - affected: 7.0.1.1 - affected: 7.0.2 - affected: 7.2.0 - affected: 7.0.2.1 - affected: 7.0.3 - affected: 7.2.0.1 - affected: 7.0.4 - affected: 7.2.1 - affected: 7.0.5 - affected: 7.3.0 - affected: 7.2.2 - affected: 7.2.3 - affected: 7.3.1 - affected: 7.2.4 - affected: 7.0.6 - affected: 7.2.5 - affected: 7.2.4.1 - affected: 7.3.1.1 - affected: 7.4.0 - affected: 7.0.6.1 - affected: 7.2.5.1 - affected: 7.4.1 - and 36 more ## References Links listed in the CVE record. They lead to other sites, which CubePath does not control. - [cisco-sa-asaftd-vpn-dos-dzv4mQFF](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-dzv4mQFF) (sec.cloudapps.cisco.com) ## Timeline 1. ID reserved Oct 8, 2025 2. Added to CISA KEV Aug 11, 2026 3. Record published Aug 11, 2026 4. Record last updated Sep 16, 2026 ## Look up another CVE ## About CubePath CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection. [Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection) Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:10 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)