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CVE-2026-20236

Multiple Cisco Products Snort 3 Software Hardening Release: October 2026

No known exploitation. EPSS puts it in the 38th percentile. No fix published yet.

CVSS 3.17.5HighEPSS percentile38th0.4% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFixNone yetNo fix or workaround published

Published Updated Sources: CVE.org, NVD

NVD CVE.org

What to do

No fixed build or workaround is published yet. Limit exposure and watch for a patch.

  • Cisco Cyber VisionAffected: 3.0.0Upgrade to: not statedAffected: 3.0.2Upgrade to: not statedAffected: 3.0.3Upgrade to: not statedAffected: 3.0.1Upgrade to: not stated + 61 more branchesStated by: CVE record
  • Cisco Open Source Snort3Affected: 3.12.2.0Upgrade to: not statedAffected: 3.1.2.0Upgrade to: not statedAffected: 3.1.3.0Upgrade to: not statedAffected: 3.1.4.0Upgrade to: not stated + 101 more branchesStated by: CVE record
  • Cisco Secure Firewall Threat Defense SoftwareAffected: 7.0.0Upgrade to: not statedAffected: 7.0.0.1Upgrade to: not statedAffected: 7.0.1Upgrade to: not statedAffected: 7.0.1.1Upgrade to: not stated + 56 more branchesStated by: CVE record
  • Cisco UTD SNORT IPS Engine SoftwareAffected: 17.12.1aUpgrade to: not statedAffected: 17.12.2Upgrade to: not statedAffected: 17.13.1aUpgrade to: not statedAffected: 17.12.3Upgrade to: not stated + 34 more branchesStated by: CVE record

Versions as the sources state them. Full version matrix after sign-in

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What it is

From the CVE record

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-2026-20236 are related to issues concerning incorrect calculation that are grouped under the Common Weakness Enumeration (CWE) Base CWE-682.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS38th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.4% chance of exploitation activity in the next 30 days, which ranks it in the 38th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

4 events over 5 days, from the signal feeds we watch.

  1. Record updated
  2. Record updated
  3. Publishedweakness classified

Affected products

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Scored 7.5 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality NoneNo confidentiality impact
  • Integrity NoneNo integrity impact
  • Availability HighTotal denial of service — the component is completely unavailable

Weaknesses

Sources

References in the record

In the news

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