CVE-2026-20043

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 v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.2 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-snort3-ybgmhTQe

Configurations

No configuration.

History

26 Oct 2026, 10:10

Type	Values Removed	Values Added
Summary		(es) Como parte del compromiso continuo de Cisco con la seguridad proactiva y la calidad del producto, el equipo de ingeniería del software de código abierto Snort 3, propiedad de Cisco, ha llevado a cabo una revisión de seguridad interna exhaustiva. Esta revisión dio como resultado lanzamientos de fortalecimiento del software que abordan múltiples vulnerabilidades descubiertas internamente. Las vulnerabilidades rastreadas por CVE-2026-20043 están relacionadas con problemas de escrituras fuera de límites que se agrupan bajo la Enumeración de Vulnerabilidades Comunes (CWE) Base CWE-787.

21 Oct 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 17:18

Updated : 2026-10-26 10:10

NVD link : CVE-2026-20043

Mitre link : CVE-2026-20043

CVE.ORG link : CVE-2026-20043

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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"affected", "version": "26.1.1"}, {"status": "affected", "version": "17.15.5"}, {"status": "affected", "version": "17.15.5a"}, {"status": "affected", "version": "17.12.7"}, {"status": "affected", "version": "17.12.7a"}, {"status": "affected", "version": "17.12.7b"}, {"status": "affected", "version": "17.9.9"}, {"status": "affected", "version": "17.18.3a"}, {"status": "affected", "version": "17.12.8"}, {"status": "affected", "version": "17.15.6"}, {"status": "affected", "version": "17.18.4"}, {"status": "affected", "version": "26.1.2"}, {"status": "affected", "version": "17.9.10"}], "defaultStatus": "unknown"}]}], "published": "2026-10-21T17:18:27.087", "references": [{"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-snort3-ybgmhTQe", "source": "psirt@cisco.com"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "psirt@cisco.com", "description": [{"lang": "en", "value": "CWE-787"}]}], "descriptions": [{"lang": "en", "value": "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.\r\n\r\nThe 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."}, {"lang": "es", "value": "Como parte del compromiso continuo de Cisco con la seguridad proactiva y la calidad del producto, el equipo de ingenier\u00eda del software de c\u00f3digo abierto Snort 3, propiedad de Cisco, ha llevado a cabo una revisi\u00f3n de seguridad interna exhaustiva. Esta revisi\u00f3n dio como resultado lanzamientos de fortalecimiento del software que abordan m\u00faltiples vulnerabilidades descubiertas internamente.\n\nLas vulnerabilidades rastreadas por CVE-2026-20043 est\u00e1n relacionadas con problemas de escrituras fuera de l\u00edmites que se agrupan bajo la Enumeraci\u00f3n de Vulnerabilidades Comunes (CWE) Base CWE-787."}], "lastModified": "2026-10-26T10:10:00.140", "sourceIdentifier": "psirt@cisco.com"}