High 7.5Published Oct 21, 2026

CVE-2026-20356Multiple Cisco Products Snort 3 Software Hardening Release: October 2026

Updated under an hour ago (Oct 27, 2026, 12:23 AM ET)

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It affects Cisco Cyber Vision and 3 other products. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.44%, higher than 38% of scored CVEs.

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Every CVE for Cisco Cyber Vision

Exploited in the last 30 days

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco owned Open Source Snort 3 Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20356 are related to issues concerning uncontrolled resource consumption that are grouped under the Common Weakness Enumeration (CWE) Base CWE-400.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-400
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.44% (percentile 38)
Assigned by: cisco
NVD analysis: Awaiting Analysis
Record last updated: Oct 22, 2026
First seen by InfoSec Signals: Oct 21, 2026

Affected products

Affected products

Cisco Cisco Cyber Vision cisco:cyber_vision (from the name)	3.0.0; 3.0.2; 3.0.3; 3.0.1; 3.1.0; 3.0.4; 3.1.1; 3.1.2; and 57 more ranges	CNA record
Cisco Cisco Open Source Snort3 cisco:open_source_snort3 (from the name)	3.12.2.0; 3.1.2.0; 3.1.3.0; 3.1.4.0; 3.1.5.0; 3.1.6.0; 3.1.7.0; 3.1.8.0; and 97 more ranges	CNA record
Cisco Cisco Secure Firewall Threat Defense (FTD) Software cisco:secure_firewall_threat_defense_ftd_software (from the name)	7.0.0; 7.0.0.1; 7.0.1; 7.0.1.1; 7.0.2; 7.2.0; 7.0.2.1; 7.0.3; and 52 more ranges	CNA record
Cisco Cisco UTD SNORT IPS Engine Software cisco:utd_snort_ips_engine_software (from the name)	17.12.1a; 17.12.2; 17.13.1a; 17.12.3; 17.14.1a; 17.12.4; 17.12.3a; 17.15.1a; and 30 more ranges	CNA record

References

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-snort3-ybgmhTQe

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.