Buffer overflow in Cisco Cyber Vision
CVE-2026-20053
Multiple Cisco products are affected by a vulnerability in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash. This vulnerability is due to improper range checking when decompressing VBA data, which is user controlled. An attacker could exploit this vulnerability by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause an overflow of heap data, which could cause a DoS condition.
Vulnerability class: Buffer Overflow
EPSS: 0.004 (34.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L.
Affected products
- Cisco Cyber Vision — versions 3.0.0, 3.0.2, 3.0.3
- Cisco Secure Firewall Threat Defense (Ftd) Software — versions 7.2.0, 7.2.0.1, 7.2.1
- Cisco Utd Snort Ips Engine Software — versions 17.12.1a, 17.9.4, 17.12.2
- Cisco Cyber_vision — versions 3.0.0, 3.0.1, 3.0.2
- Cisco Secure_firewall_threat_defense — versions 7.2.0, 7.2.0.1, 7.2.1
- Cisco Snort
- Cisco Unified_threat_defense_snort_intrusion_prevention_system_engine — versions 17.12.1a, 17.12.2, 17.12.3
Weakness classification (CWE)
References
- psirt@cisco.com (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-20053?
- CVE-2026-20053 is a medium-severity vulnerability in Cisco Cyber Vision, classified under Heap-based Buffer Overflow. CVSS score: 5.8/10. Published 2026-03-04.
- How severe is CVE-2026-20053?
- Medium severity. CVSS v3 base score is 5.8 out of 10.