CVE-2026-20053

Medium

Description

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.

SeverityMedium
CVSS5.8
Exploit probability—
ProductCisco Snort
PublishedMar 4, 2026
First seenMar 4, 2026
Weakness typeCWE-122CWE-122

How to fix

Update
  • cisco snort3.9.3.0 or later

Affected products

ProductAffected versionsFixed in
cisco snort3.0.0-233 ≤ v < 3.9.3.03.9.3.0
cisco cyber_vision3.0.0, 3.0.1, 3.0.2, 3.0.3, 3.0.4, 3.0.5, 3.0.6, 3.1.0, 3.1.1, 3.1.2, 3.2.0, 3.2.1, 3.2.2, 3.2.3, 3.2.4, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.1.0, 4.1.1, 4.1.2, 4.1.3, 4.1.4, 4.1.5, 4.1.6, 4.1.7, 4.2.0, 4.2.1, 4.2.2, 4.2.3, 4.2.4, 4.2.6, 4.3.0, 4.3.1, 4.3.2, 4.3.3, 4.4.0, 4.4.1, 4.4.2, 4.4.3, 5.0.0, 5.0.1, 5.0.2, 5.1.0, 5.1.1, 5.1.2, 5.1.3, 5.2.0, 5.2.1, 5.3.0, 5.3.1, 5.3.2—
cisco secure_firewall_threat_defense7.2.0, 7.2.0.1, 7.2.1, 7.2.2, 7.2.3, 7.2.4, 7.2.4.1, 7.2.5, 7.2.5.1, 7.2.5.2, 7.2.6, 7.2.7, 7.2.8, 7.2.8.1, 7.2.9, 7.2.10, 7.2.10.2, 7.3.0, 7.3.1, 7.3.1.1, 7.3.1.2, 7.4.0, 7.4.1, 7.4.1.1, 7.4.2, 7.4.2.1, 7.4.2.2, 7.4.2.3, 7.4.2.4, 7.4.3, 7.6.0, 7.6.1, 7.6.2, 7.6.2.1, 7.7.0, 7.7.10, 7.7.10.1—
cisco unified_threat_defense_snort_intrusion_prevention_system_engine17.9.4, 17.9.5e, 17.12.1a, 17.12.2, 17.12.3, 17.12.3a, 17.12.4, 17.12.4a, 17.12.4b, 17.12.5, 17.12.5a, 17.12.5b, 17.12.5c, 17.12.5d, 17.12.6, 17.13.1a, 17.14.1a, 17.15.1a, 17.15.2a, 17.15.2c, 17.15.3, 17.15.3a, 17.15.4, 17.15.4c, 17.16.1a, 17.17.1, 17.18.1, 17.18.1a, 17.18.2—

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CVE-2026-20053 · Cisco Snort · Dark Radar