As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco owned Open Source Snort 3
Source GCVE Database
Not known to be exploited · CVSS 7.5 High.
Data as of 7 Nov 2026, 19:34 UTC
Thin evidence
One scorer or none| CNA (cisco) | CVSS 3.1 | 7.5 |
|---|
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 21 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 7 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| CiscoCisco Cyber Vision | Affected
| Fixed in– |
| CiscoCisco Open Source Snort3 | Affected
| Fixed in– |
| CiscoCisco Secure Firewall Threat Defense (FTD) Software | Affected
| Fixed in– |
| CiscoCisco UTD SNORT IPS Engine Software | Affected
| Fixed in– |
AI-suggested
Cisco has performed a comprehensive internal security review and issued software hardening releases to address these vulnerabilities. Users should consult Cisco's official advisories for updates and apply any released fixes promptly once available.
Description
CVE-2026-20236 is a high-severity vulnerability in Cisco's Open Source Snort 3 software related to incorrect calculation issues classified under CWE-682. Cisco's internal security review identified multiple vulnerabilities, including this one, leading to software hardening releases. No specific affected versions or patch details are provided in the available data. The vulnerability has a CVSS score of 7.5 with an impact on availability but no confirmed exploitation in the wild.