VulnTideExploited vulnerabilities, by vendor. Data as of .
Not in CISA KEVPublished CVSS 9.0 criticalEPSS 0.4% probability of exploitation in 30 days
Cisco

CVE-2026-20043: Multiple Cisco Products Snort 3 Software Hardening Release: October 2026

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?
0.4%

Up from 0.3% on .

EPSS score, percentile 30.2 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?
9.0 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

  • 3.0.0
  • 3.0.2
  • 3.0.3
  • 3.0.1
  • 3.1.0
  • 3.0.4

and 42 more in the table below

Versions by product

Source: CISA KEV 2026.10.28, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

As listed in the CVE record.

Cisco Cisco Cyber Vision
StatusVersions
Affected3.0.0
Affected3.0.2
Affected3.0.3
Affected3.0.1
Affected3.1.0
Affected3.0.4
Affected3.1.1
Affected3.1.2
Affected3.2.0
Affected3.0.5
Affected3.2.1
Affected3.0.6

Versions not listed are: unknown.

And 53 more version entries in the CVE record.

Cisco Cisco Open Source Snort3
StatusVersions
Affected3.12.2.0
Affected3.1.2.0
Affected3.1.3.0
Affected3.1.4.0
Affected3.1.5.0
Affected3.1.6.0
Affected3.1.7.0
Affected3.1.8.0
Affected3.1.9.0
Affected3.1.10.0
Affected3.1.12.0
Affected3.1.13.0

Versions not listed are: unknown.

And 93 more version entries in the CVE record.

Cisco Cisco Secure Firewall Threat Defense (FTD) Software
StatusVersions
Affected7.0.0
Affected7.0.0.1
Affected7.0.1
Affected7.0.1.1
Affected7.0.2
Affected7.0.2.1
Affected7.0.3
Affected7.2.0.1
Affected7.0.4
Affected7.2.1
Affected7.0.5
Affected7.3.0

Versions not listed are: unknown.

And 47 more version entries in the CVE record.

Cisco Cisco UTD SNORT IPS Engine Software
StatusVersions
Affected17.3.1a
Affected17.3.2
Affected17.4.1a
Affected17.5.1
Affected17.3.3
Affected17.5.1a
Affected17.3.4
Affected17.3.4a
Affected17.4.2
Affected17.4.1b
Affected17.6.1a
Affected17.7.1a

Versions not listed are: unknown.

And 71 more version entries in the CVE record.

Source: CVE List, as of . About the data.

About this vulnerability

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-o…

Summary: CVE record, as of .

  • CISA has not added CVE-2026-20043 to its Known Exploited Vulnerabilities (KEV) catalog, as of 28 Oct 2026.
  • The CVE record was published on 21 Oct 2026.
  • The CVE record carries a CVSS v3.1 base score of 9.0 (Critical), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.4% (percentile 30.2), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
  • CISA's SSVC assessment in the CVE record: exploitation none, automatable no, technical impact total.

Source: CISA KEV 2026.10.28, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.

Description

Multiple Cisco Products Snort 3 Software Hardening Release: October 2026

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.

Source: CVE List, as of . About the data.

Weakness

CWE-787

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.

Timeline

DateEvent
CVE record published
CVE record last updated

References

1

Known exploited Cisco vulnerabilities

  • CVE-2026-76519: Cisco Secure Email Gateway Relative Path Traversal Vulnerability (added )
  • CVE-2026-76504: Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability (added )
  • CVE-2026-76460: Cisco Identity Services Engine Incorrect Use of Privileged APIs Vulnerability (added )
  • CVE-2026-76461: Cisco Secure Email Gateway SQL Injection Vulnerability (added )
  • CVE-2026-20079: Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability (added )