CVE-2026-20053
MediumCVSS 5.8Exploitation Probability (EPSS)
Low risk35th percentile - higher than 35% of all known CVEs
Summary
A vulnerability in the VBA feature of the Snort 3 engine in multiple Cisco products allows an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash. This is due to improper range checking when decompressing user-controlled VBA data. A successful exploit could cause an overflow of heap data, leading to a DoS condition.
Risk Assessment
An attacker can cause the detection engine to crash, leading to unavailability of network protection services and potential bypass of malicious traffic.
Recommendation
Apply security updates provided by Cisco for affected products.
Other vulnerabilities in Cisco Snort 3
See all- CVE-2026-20057Medium
A vulnerability in the VBA feature of the Snort 3 engine in multiple Cisco products allows an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash. This is due to lack of proper error checking when decompressing VBA data. A successful exploit could cause the engine to unexpectedly restart, leading to a DoS condition.
- CVE-2026-20054Medium
A vulnerability in the VBA feature of the Snort 3 engine in multiple Cisco products allows an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash. This is due to improper error checking when decompressing VBA data. A successful exploit could cause the engine to enter an infinite loop, leading to a DoS condition.
- CVE-2022-20943Medium
Multiple vulnerabilities in the SMB2 processor of the Snort detection engine on multiple Cisco products could allow an unauthenticated, remote attacker to bypass configured policies or cause a denial of service (DoS) condition. This is due to improper management of system resources when processing SMB2 traffic. An attacker could send a high rate of SMB2 packets to trigger a reload of the Snort process. With preserve-connection enabled (default), policy bypass and malicious payload delivery are also possible.
- CVE-2021-1495Medium
A vulnerability in the Snort detection engine of multiple Cisco products could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The issue is due to incorrect handling of specific HTTP header parameters. An attacker could exploit this by sending crafted HTTP packets through an affected device, bypassing the policy and delivering a malicious payload.
Original NVD description (English source)
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.