CVE-2026-20043
Awaiting Analysis Awaiting Analysis - Queue

Out-of-Bounds Write in Cisco Snort 3

Vulnerability report for CVE-2026-20043, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-10-21

Last updated on: 2026-10-21

Assigner: Cisco Systems, Inc.

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.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-10-21
Last Modified
2026-10-21
Generated
2026-10-21
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 312 associated CPEs
Vendor Product Version / Range
Cisco Cisco Cyber Vision 3.0.0
Cisco Cisco Cyber Vision 3.0.2
Cisco Cisco Cyber Vision 3.0.3
Cisco Cisco Cyber Vision 3.0.1
Cisco Cisco Cyber Vision 3.1.0
Cisco Cisco Cyber Vision 3.0.4
Cisco Cisco Cyber Vision 3.1.1
Cisco Cisco Cyber Vision 3.1.2
Cisco Cisco Cyber Vision 3.2.0
Cisco Cisco Cyber Vision 3.0.5
Cisco Cisco Cyber Vision 3.2.1
Cisco Cisco Cyber Vision 3.0.6
Cisco Cisco Cyber Vision 3.2.2
Cisco Cisco Cyber Vision 3.2.3
Cisco Cisco Cyber Vision 3.2.4
Cisco Cisco Cyber Vision 4.0.0
Cisco Cisco Cyber Vision 4.0.1
Cisco Cisco Cyber Vision 4.0.2
Cisco Cisco Cyber Vision 4.0.3
Cisco Cisco Cyber Vision 4.1.0
Cisco Cisco Cyber Vision 4.1.1
Cisco Cisco Cyber Vision 4.1.2
Cisco Cisco Cyber Vision 4.1.3
Cisco Cisco Cyber Vision 4.1.4
Cisco Cisco Cyber Vision 4.2.0
Cisco Cisco Cyber Vision 4.2.1
Cisco Cisco Cyber Vision 4.1.5
Cisco Cisco Cyber Vision 4.2.2
Cisco Cisco Cyber Vision 4.2.X
Cisco Cisco Cyber Vision 4.2.3
Cisco Cisco Cyber Vision 4.2.4
Cisco Cisco Cyber Vision 4.2.6
Cisco Cisco Cyber Vision 4.1.6
Cisco Cisco Cyber Vision 4.3.0
Cisco Cisco Cyber Vision 4.3.1
Cisco Cisco Cyber Vision 4.3.2
Cisco Cisco Cyber Vision 4.3.3
Cisco Cisco Cyber Vision 4.4.0
Cisco Cisco Cyber Vision 4.4.1
Cisco Cisco Cyber Vision 4.4.2
Cisco Cisco Cyber Vision 4.4.3
Cisco Cisco Cyber Vision 4.1.7
Cisco Cisco Cyber Vision 5.0.0
Cisco Cisco Cyber Vision 5.0.1
Cisco Cisco Cyber Vision 5.0.2
Cisco Cisco Cyber Vision 5.1.0
Cisco Cisco Cyber Vision 5.1.1
Cisco Cisco Cyber Vision 5.1.2
Cisco Cisco Cyber Vision 5.1.3
Cisco Cisco Cyber Vision 5.2.0
Cisco Cisco Cyber Vision 5.2.1
Cisco Cisco Cyber Vision 5.3.0
Cisco Cisco Cyber Vision 5.3.1
Cisco Cisco Cyber Vision 5.3.2
Cisco Cisco Cyber Vision 5.3.3
Cisco Cisco Cyber Vision 5.5.1
Cisco Cisco Cyber Vision 5.6.1
Cisco Cisco Cyber Vision 5.4.0
Cisco Cisco Cyber Vision 5.4.1
Cisco Cisco Cyber Vision 5.4.2
Cisco Cisco Cyber Vision 5.7.0
Cisco Cisco Cyber Vision 5.8.1
Cisco Cisco Cyber Vision 5.7.1
Cisco Cisco Cyber Vision 5.8.0
Cisco Cisco Cyber Vision 5.5.2
Cisco Cisco Open Source Snort3 3.12.2.0
Cisco Cisco Open Source Snort3 3.1.2.0
Cisco Cisco Open Source Snort3 3.1.3.0
Cisco Cisco Open Source Snort3 3.1.4.0
Cisco Cisco Open Source Snort3 3.1.5.0
Cisco Cisco Open Source Snort3 3.1.6.0
Cisco Cisco Open Source Snort3 3.1.7.0
Cisco Cisco Open Source Snort3 3.1.8.0
Cisco Cisco Open Source Snort3 3.1.9.0
Cisco Cisco Open Source Snort3 3.1.10.0
Cisco Cisco Open Source Snort3 3.1.12.0
Cisco Cisco Open Source Snort3 3.1.13.0
Cisco Cisco Open Source Snort3 3.1.14.0
Cisco Cisco Open Source Snort3 3.1.15.0
Cisco Cisco Open Source Snort3 3.1.16.0
Cisco Cisco Open Source Snort3 3.1.17.0
Cisco Cisco Open Source Snort3 3.1.18.0
Cisco Cisco Open Source Snort3 3.1.19.0
Cisco Cisco Open Source Snort3 3.1.20.0
Cisco Cisco Open Source Snort3 3.1.21.0
Cisco Cisco Open Source Snort3 3.1.22.0
Cisco Cisco Open Source Snort3 3.1.23.0
Cisco Cisco Open Source Snort3 3.1.24.0
Cisco Cisco Open Source Snort3 3.1.25.0
Cisco Cisco Open Source Snort3 3.1.27.0
Cisco Cisco Open Source Snort3 3.1.28.0
Cisco Cisco Open Source Snort3 3.1.29.0
Cisco Cisco Open Source Snort3 3.1.30.0
Cisco Cisco Open Source Snort3 3.1.31.0
Cisco Cisco Open Source Snort3 3.1.32.0
Cisco Cisco Open Source Snort3 3.1.36.0
Cisco Cisco Open Source Snort3 3.1.38.0
Cisco Cisco Open Source Snort3 3.1.39.0
Cisco Cisco Open Source Snort3 3.1.40.0
Cisco Cisco Open Source Snort3 3.1.41.0
Cisco Cisco Open Source Snort3 3.1.42.0
Cisco Cisco Open Source Snort3 3.1.43.0
Cisco Cisco Open Source Snort3 3.1.45.0
Cisco Cisco Open Source Snort3 3.1.47.0
Cisco Cisco Open Source Snort3 3.1.48.0
Cisco Cisco Open Source Snort3 3.1.50.0
Cisco Cisco Open Source Snort3 3.1.51.0
Cisco Cisco Open Source Snort3 3.1.52.0
Cisco Cisco Open Source Snort3 3.1.53.0
Cisco Cisco Open Source Snort3 3.1.55.0
Cisco Cisco Open Source Snort3 3.1.56.0
Cisco Cisco Open Source Snort3 3.1.57.0
Cisco Cisco Open Source Snort3 3.1.58.0
Cisco Cisco Open Source Snort3 3.1.59.0
Cisco Cisco Open Source Snort3 3.1.60.0
Cisco Cisco Open Source Snort3 3.1.61.0
Cisco Cisco Open Source Snort3 3.1.62.0
Cisco Cisco Open Source Snort3 3.1.63.0
Cisco Cisco Open Source Snort3 3.1.64.0
Cisco Cisco Open Source Snort3 3.1.65.0
Cisco Cisco Open Source Snort3 3.1.66.0
Cisco Cisco Open Source Snort3 3.1.67.0
Cisco Cisco Open Source Snort3 3.1.69.0
Cisco Cisco Open Source Snort3 3.1.70.0
Cisco Cisco Open Source Snort3 3.1.71.0
Cisco Cisco Open Source Snort3 3.1.72.0
Cisco Cisco Open Source Snort3 3.1.73.0
Cisco Cisco Open Source Snort3 3.1.74.0
Cisco Cisco Open Source Snort3 3.1.75.0
Cisco Cisco Open Source Snort3 3.1.76.0
Cisco Cisco Open Source Snort3 3.1.77.0
Cisco Cisco Open Source Snort3 3.1.78.0
Cisco Cisco Open Source Snort3 3.1.81.0
Cisco Cisco Open Source Snort3 3.1.82.0
Cisco Cisco Open Source Snort3 3.1.83.0
Cisco Cisco Open Source Snort3 3.1.84.0
Cisco Cisco Open Source Snort3 3.2.1.0
Cisco Cisco Open Source Snort3 3.2.2.0
Cisco Cisco Open Source Snort3 3.3.0.0
Cisco Cisco Open Source Snort3 3.3.1.0
Cisco Cisco Open Source Snort3 3.3.2.0
Cisco Cisco Open Source Snort3 3.3.3.0
Cisco Cisco Open Source Snort3 3.3.4.0
Cisco Cisco Open Source Snort3 3.3.5.0
Cisco Cisco Open Source Snort3 3.3.7.0
Cisco Cisco Open Source Snort3 3.5.0.0
Cisco Cisco Open Source Snort3 3.5.1.0
Cisco Cisco Open Source Snort3 3.8.1.0
Cisco Cisco Open Source Snort3 3.6.0.0
Cisco Cisco Open Source Snort3 3.6.2.0
Cisco Cisco Open Source Snort3 3.9.3.0
Cisco Cisco Open Source Snort3 3.7.2.0
Cisco Cisco Open Source Snort3 3.7.0.0
Cisco Cisco Open Source Snort3 3.9.6.0
Cisco Cisco Open Source Snort3 3.10.0.0
Cisco Cisco Open Source Snort3 3.10.2.0
Cisco Cisco Open Source Snort3 3.7.4.0
Cisco Cisco Open Source Snort3 3.9.0.0
Cisco Cisco Open Source Snort3 3.5.2.0
Cisco Cisco Open Source Snort3 3.12.1.0
Cisco Cisco Open Source Snort3 3.6.1.0
Cisco Cisco Open Source Snort3 3.9.2.0
Cisco Cisco Open Source Snort3 3.6.3.0
Cisco Cisco Open Source Snort3 3.9.5.0
Cisco Cisco Open Source Snort3 3.7.1.0
Cisco Cisco Open Source Snort3 3.9.7.0
Cisco Cisco Open Source Snort3 3.7.3.0
Cisco Cisco Open Source Snort3 3.10.1.0
Cisco Cisco Open Source Snort3 3.9.1.0
Cisco Cisco Open Source Snort3 3.11.1.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.5
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.3.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.3.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.6
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.4.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.3.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.6.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.6
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.6.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.7
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.3.1.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.8
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.6.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.8.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.6.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.9
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.7
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.7.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.10
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.6.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.8
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.6.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.7.10
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.7.11
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.8.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.6.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.7.10.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.10.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.6.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 10.0.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.9
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.2.11
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.4.7
Cisco Cisco UTD SNORT IPS Engine Software 17.3.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.3.2
Cisco Cisco UTD SNORT IPS Engine Software 17.4.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.5.1
Cisco Cisco UTD SNORT IPS Engine Software 17.3.3
Cisco Cisco UTD SNORT IPS Engine Software 17.5.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.3.4
Cisco Cisco UTD SNORT IPS Engine Software 17.3.4a
Cisco Cisco UTD SNORT IPS Engine Software 17.4.2
Cisco Cisco UTD SNORT IPS Engine Software 17.4.1b
Cisco Cisco UTD SNORT IPS Engine Software 17.6.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.7.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.6.2
Cisco Cisco UTD SNORT IPS Engine Software 17.8.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.3.5
Cisco Cisco UTD SNORT IPS Engine Software 17.6.3
Cisco Cisco UTD SNORT IPS Engine Software 17.6.3a
Cisco Cisco UTD SNORT IPS Engine Software 17.7.2
Cisco Cisco UTD SNORT IPS Engine Software 17.9.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.6.4
Cisco Cisco UTD SNORT IPS Engine Software 17.10.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.3.6
Cisco Cisco UTD SNORT IPS Engine Software 17.3.7
Cisco Cisco UTD SNORT IPS Engine Software 17.9.2a
Cisco Cisco UTD SNORT IPS Engine Software 17.6.5
Cisco Cisco UTD SNORT IPS Engine Software 17.11.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.3a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.4
Cisco Cisco UTD SNORT IPS Engine Software 17.6.6
Cisco Cisco UTD SNORT IPS Engine Software 17.3.8
Cisco Cisco UTD SNORT IPS Engine Software 17.3.8a
Cisco Cisco UTD SNORT IPS Engine Software 17.6.6a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.4a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.2
Cisco Cisco UTD SNORT IPS Engine Software 17.13.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.5a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.3
Cisco Cisco UTD SNORT IPS Engine Software 17.6.7
Cisco Cisco UTD SNORT IPS Engine Software 17.14.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.4
Cisco Cisco UTD SNORT IPS Engine Software 17.12.3a
Cisco Cisco UTD SNORT IPS Engine Software 17.15.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.6.8
Cisco Cisco UTD SNORT IPS Engine Software 17.9.6
Cisco Cisco UTD SNORT IPS Engine Software 17.6.8a
Cisco Cisco UTD SNORT IPS Engine Software 17.16.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.5e
Cisco Cisco UTD SNORT IPS Engine Software 17.12.4a
Cisco Cisco UTD SNORT IPS Engine Software 17.15.2c
Cisco Cisco UTD SNORT IPS Engine Software 17.9.5f
Cisco Cisco UTD SNORT IPS Engine Software 17.12.4b
Cisco Cisco UTD SNORT IPS Engine Software 17.15.2a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.5
Cisco Cisco UTD SNORT IPS Engine Software 17.17.1
Cisco Cisco UTD SNORT IPS Engine Software 17.12.5a
Cisco Cisco UTD SNORT IPS Engine Software 17.9.7a
Cisco Cisco UTD SNORT IPS Engine Software 17.15.3a
Cisco Cisco UTD SNORT IPS Engine Software 17.15.3
Cisco Cisco UTD SNORT IPS Engine Software 17.12.5b
Cisco Cisco UTD SNORT IPS Engine Software 17.12.5c
Cisco Cisco UTD SNORT IPS Engine Software 17.15.4
Cisco Cisco UTD SNORT IPS Engine Software 17.9.7b
Cisco Cisco UTD SNORT IPS Engine Software 17.18.1
Cisco Cisco UTD SNORT IPS Engine Software 17.18.1a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.6
Cisco Cisco UTD SNORT IPS Engine Software 17.9.8
Cisco Cisco UTD SNORT IPS Engine Software 17.15.4c
Cisco Cisco UTD SNORT IPS Engine Software 17.12.5d
Cisco Cisco UTD SNORT IPS Engine Software 17.18.2
Cisco Cisco UTD SNORT IPS Engine Software 26.1.1
Cisco Cisco UTD SNORT IPS Engine Software 17.15.5
Cisco Cisco UTD SNORT IPS Engine Software 17.15.5a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.7
Cisco Cisco UTD SNORT IPS Engine Software 17.12.7a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.7b
Cisco Cisco UTD SNORT IPS Engine Software 17.9.9
Cisco Cisco UTD SNORT IPS Engine Software 17.18.3a
Cisco Cisco UTD SNORT IPS Engine Software 17.12.8
Cisco Cisco UTD SNORT IPS Engine Software 17.15.6
Cisco Cisco UTD SNORT IPS Engine Software 17.18.4
Cisco Cisco UTD SNORT IPS Engine Software 26.1.2
Cisco Cisco UTD SNORT IPS Engine Software 17.9.10

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-787 The product writes data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

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