What’s Vulnerable › Vulnerabilities
CVE-2026-20043: Multiple Cisco Products Snort 3 Software Hardening Release: October 2026
- Severity: critical (CVSS 9.0 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-10-21 · updated 2026-10-26
- Weakness: CWE-787
Description
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-2026-20043 are related to issues concerning out-of-bounds writes that are grouped under the Common Weakness Enumeration (CWE) Base CWE-787.
Affected products
- Cisco Open Source Snort3: 3.12.2.0, 3.1.2.0, 3.1.3.0, 3.1.4.0, 3.1.5.0, 3.1.6.0 (+99)
- Cisco Cyber Vision: 3.0.0, 3.0.2, 3.0.3, 3.0.1, 3.1.0, 3.0.4 (+59)
- Cisco Firepower Threat Defense Software: 7.0.0, 7.0.0.1, 7.0.1, 7.0.1.1, 7.0.2, 7.0.2.1 (+53)
- Cisco UTD SNORT IPS Engine Software: 17.3.1a, 17.3.2, 17.4.1a, 17.5.1, 17.3.3, 17.5.1a (+77)
In the news
- Multiple Cisco Products Snort 3 Security Hardening Release: October 2026
- Cisco Advance Notification for Publication of October 21, 2026, Security Advisories
References
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