Riskcovery

CVE-2026-20218

Cisco Secure Firewall Threat Defense Snort 3 Visual Basic for Applications Buffer Overflow Denial of Service Vulnerability

State
Published
Severity
5.8 Medium
Published
Oct 21, 2026
Updated
Oct 22, 2026
Reserved
Oct 8, 2025

Read the record on cve.org

Description

A vulnerability in the Snort 3 Visual Basic for Applications (VBA) Decompression Engine of multiple Cisco products could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition.  

This vulnerability is due to improper range checking when Snort 3 decompresses VBA data, which is user controlled. An attacker could exploit this vulnerability by sending crafted VBA data to the Snort 3 Detection Engine of a targeted device. A successful exploit could allow the attacker to cause an overflow of stack data, which could result in a DoS condition.

Scores

CVSSScoreVectorSource
3.15.8 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lcisco

Weaknesses

  • CWE-121 Stack-based Buffer Overflow

Affected Products

ProductVersions
Cisco Open Source Snort3Cisco
  • 3.12.2.0Affected
  • 3.1.2.0Affected
  • 3.1.3.0Affected
  • 3.1.4.0Affected
  • 3.1.5.0Affected
  • 3.1.6.0Affected
  • 3.1.7.0Affected
  • 3.1.8.0Affected
  • 3.1.9.0Affected
  • 3.1.10.0Affected
  • 3.1.12.0Affected
  • 3.1.13.0Affected
  • 3.1.14.0Affected
  • 3.1.15.0Affected
  • 3.1.16.0Affected
  • 3.1.17.0Affected
  • 3.1.18.0Affected
  • 3.1.19.0Affected
  • 3.1.20.0Affected
  • 3.1.21.0Affected
  • 3.1.22.0Affected
  • 3.1.23.0Affected
  • 3.1.24.0Affected
  • 3.1.25.0Affected
  • 3.1.27.0Affected
  • and 80 more versions
Cisco Secure Firewall Threat Defense (FTD) SoftwareCisco
  • 7.2.0Affected
  • 7.2.0.1Affected
  • 7.2.1Affected
  • 7.3.0Affected
  • 7.2.2Affected
  • 7.2.3Affected
  • 7.3.1Affected
  • 7.2.4Affected
  • 7.2.5Affected
  • 7.2.4.1Affected
  • 7.3.1.1Affected
  • 7.4.0Affected
  • 7.2.5.1Affected
  • 7.4.1Affected
  • 7.2.6Affected
  • 7.4.1.1Affected
  • 7.2.7Affected
  • 7.2.5.2Affected
  • 7.3.1.2Affected
  • 7.2.8Affected
  • 7.6.0Affected
  • 7.4.2Affected
  • 7.2.8.1Affected
  • 7.4.2.1Affected
  • 7.2.9Affected
  • and 18 more versions
Cisco UTD SNORT IPS Engine SoftwareCisco
  • 17.12.1aAffected
  • 17.12.2Affected
  • 17.13.1aAffected
  • 17.12.3Affected
  • 17.14.1aAffected
  • 17.12.4Affected
  • 17.12.3aAffected
  • 17.15.1aAffected
  • 17.16.1aAffected
  • 17.12.4aAffected
  • 17.15.2cAffected
  • 17.12.4bAffected
  • 17.15.2aAffected
  • 17.12.5Affected
  • 17.17.1Affected
  • 17.12.5aAffected
  • 17.15.3aAffected
  • 17.15.3Affected
  • 17.12.5bAffected
  • 17.12.5cAffected
  • 17.15.4Affected
  • 17.18.1Affected
  • 17.18.1aAffected
  • 17.12.6Affected
  • 17.15.4cAffected
  • and 13 more versions

References

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