CVE record · CVE-2026-20221

Multiple Cisco Products Snort 3 Generic Routing Encapsulation Denial of Service Vulnerabilities

CVSS 5.8 MediumEPSS 0.0058 · 47th percentile

Published by the CVE Program (CNA: cisco) at 21 Oct 2026, 16:12 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
VendorProductVersions
Cisco Cisco Cyber Vision
  • affected 3.0.0
  • affected 3.0.2
  • affected 3.0.3
  • affected 3.0.1
  • affected 3.1.0
  • affected 3.0.4
  • affected 3.1.1
  • affected 3.1.2
  • affected 3.2.0
  • affected 3.0.5
  • affected 3.2.1
  • affected 3.0.6
  • and 49 more
Other versions: unknown
Cisco Cisco Open Source Snort3
  • affected 3.12.2.0
  • affected 3.1.2.0
  • affected 3.1.3.0
  • affected 3.1.4.0
  • affected 3.1.5.0
  • affected 3.1.6.0
  • affected 3.1.7.0
  • affected 3.1.8.0
  • affected 3.1.9.0
  • affected 3.1.10.0
  • affected 3.1.12.0
  • affected 3.1.13.0
  • and 93 more
Other versions: unknown
Cisco Cisco Secure Firewall Threat Defense (FTD) Software
  • affected 7.0.0
  • affected 7.0.0.1
  • affected 7.0.1
  • affected 7.0.1.1
  • affected 7.0.2
  • affected 7.2.0
  • affected 7.0.2.1
  • affected 7.0.3
  • affected 7.2.0.1
  • affected 7.0.4
  • affected 7.2.1
  • affected 7.0.5
  • and 48 more
Other versions: unknown
Cisco Cisco Umbrella Insights Virtual Appliance
  • affected 2.6.0
  • affected 2.5.6
  • affected 2.5
  • affected 2.4.12
  • affected 2.7
  • affected 2.6.2
  • affected 2.5.5
  • affected 2.5.4
  • affected 2.8
  • affected 2.6.1
  • affected 2.5.7
  • affected 1.5.4
  • and 61 more
Other versions: unknown
Cisco Cisco UTD SNORT IPS Engine Software
  • affected 3.17.1S
  • affected 16.12.3
  • affected Fuji-16.9.5
  • affected 16.12.4
  • affected 17.3.1a
  • affected 16.6.6
  • affected 16.12.2
  • affected Fuji-16.9.6
  • affected 3.17.0S
  • affected Fuji-16.9.3
  • affected Denali-16.3.7
  • affected Fuji-16.9.2
  • and 104 more
Other versions: unknown
Identifiers
CVE-2026-20221
CNA
cisco
Weakness (CWE)
CWE-476
Published
21 Oct 2026
Updated
22 Oct 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

ScoreRatingCVSSVectorSource
5.8 Medium 3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L CNA (cisco)
  • CISA KEV Not listed.
  • EPSS 0.0058, the 47th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 21 Oct 2026. New records show when each source confirmed them.

Sources

References from the CNA

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.