Executive brief
Cisco Secure Firewall products—including the ASA appliance, Threat Defense software, and Management Center—contain multiple security vulnerabilities stemming from improper coding practices. These issues could allow attackers with network access and valid credentials to compromise firewall functionality, potentially affecting confidentiality, integrity, and availability of protected networks.
Technical details
CVE-2026-20334 is part of a grouped hardening release addressing eight related vulnerabilities (CVE-2026-20329 through CVE-2026-20336) across multiple CWE categories, including improper exception handling (CWE-703), data validation issues (CWE-707), weak protection mechanisms (CWE-693), access control flaws (CWE-284), and resource lifecycle problems (CWE-664). The vulnerability class tracked by CVE-2026-20334 specifically concerns improper adherence to coding standards (CWE-710). Exploitation requires network access and authenticated credentials (CVSS:3.1/AV:N/AC:L/PR:L). The vulnerabilities were discovered during internal Cisco security reviews and represent software hardening fixes. Patches are available; no workarounds exist.
Affected products
- Cisco Secure Firewall Adaptive Security Appliance Software <UNKNOWN>
- Cisco Secure Firewall Threat Defense Software <UNKNOWN>
- Cisco Secure Firewall Management Center Software <UNKNOWN>
Timeline
- 2026-09-16: disclosed
- 2026-09-16: advisory: Cisco Security Advisory published