CVE-2026-76459 - Vulnerability Details

- Cisco NX-OS Software Security Hardening Release: October 2026 - Out-of-bounds Write Vulnerabilities

Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco NX-OS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities.

The vulnerabilities tracked by CVE-2026-76459 are related to out-of-bounds write issues that are grouped under the Common Weakness Enumeration (CWE) CWE-787.

Published: 2026-10-07

Score: 9.8 Critical

EPSS: < 1% Very Low

KEV: No

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Cisco

Cisco NX-OS Software

unknown

Version	Status	Constraints
`8.2(5)`	affected	—
`7.3(5)D1(1)`	affected	—
`8.4(2)`	affected	—
`8.4(3)`	affected	—
`9.2(3)`	affected	—
`8.2(1)`	affected	—
`7.3(1)D1(1)`	affected	—
`9.2(2v)`	affected	—
`7.3(0)D1(1)`	affected	—
`7.3(4)D1(1)`	affected	—
`9.2(1)`	affected	—
`9.2(2t)`	affected	—
`9.2(3y)`	affected	—
`9.3(2)`	affected	—
`7.3(1)DY(1)`	affected	—
`8.1(1)`	affected	—
`8.2(2)`	affected	—
`8.3(2)`	affected	—
`7.3(2)D1(3a)`	affected	—
`9.2(4)`	affected	—
`8.1(2)`	affected	—
`7.3(3)D1(1)`	affected	—
`8.2(3)`	affected	—
`8.3(1)`	affected	—
`8.4(1)`	affected	—
`8.1(1b)`	affected	—
`7.3(0)DX(1)`	affected	—
`7.3(2)D1(1)`	affected	—
`9.3(1)`	affected	—
`7.3(2)D1(2)`	affected	—
`8.2(4)`	affected	—
`7.3(0)DY(1)`	affected	—
`9.3(1z)`	affected	—
`9.2(2)`	affected	—
`8.1(2a)`	affected	—
`7.3(2)D1(3)`	affected	—
`8.1(1a)`	affected	—
`8.4(1a)`	affected	—
`9.3(3)`	affected	—
`7.3(2)D1(1d)`	affected	—
`9.3(4)`	affected	—
`7.3(6)D1(1)`	affected	—
`8.2(6)`	affected	—
`9.3(5)`	affected	—
`8.4(2a)`	affected	—
`8.4(2b)`	affected	—
`8.5(1)`	affected	—
`9.3(6)`	affected	—
`8.4(4)`	affected	—
`7.3(7)D1(1)`	affected	—
`8.4(2c)`	affected	—
`9.3(5w)`	affected	—
`8.2(7)`	affected	—
`9.3(7)`	affected	—
`9.3(7k)`	affected	—
`7.3(8)D1(1)`	affected	—
`9.3(7a)`	affected	—
`8.2(7a)`	affected	—
`9.3(8)`	affected	—
`8.4(4a)`	affected	—
`8.4(2d)`	affected	—
`8.4(5)`	affected	—
`8.2(8)`	affected	—
`9.3(9)`	affected	—
`7.3(9)D1(1)`	affected	—
`8.4(6)`	affected	—
`8.4(2e)`	affected	—
`9.3(10)`	affected	—
`9.2(1a)`	affected	—
`8.2(9)`	affected	—
`10.3(1)`	affected	—
`8.4(7)`	affected	—
`10.3(2)`	affected	—
`8.4(6a)`	affected	—
`9.3(11)`	affected	—
`10.3(3)`	affected	—
`9.4(1)`	affected	—
`9.3(2a)`	affected	—
`8.4(2f)`	affected	—
`8.2(10)`	affected	—
`9.3(12)`	affected	—
`10.4(1)`	affected	—
`8.4(8)`	affected	—
`10.3(99w)`	affected	—
`10.3(3w)`	affected	—
`10.3(99x)`	affected	—
`10.3(3o)`	affected	—
`8.4(9)`	affected	—
`10.3(4)`	affected	—
`10.3(3p)`	affected	—
`10.3(4a)`	affected	—
`9.4(1a)`	affected	—
`10.4(2)`	affected	—
`10.3(3q)`	affected	—
`9.3(13)`	affected	—
`8.2(11)`	affected	—
`9.4(2)`	affected	—
`10.3(5)`	affected	—
`10.4(3)`	affected	—
`10.3(3x)`	affected	—
`10.3(4g)`	affected	—
`10.5(1)`	affected	—
`8.4(10)`	affected	—
`9.4(2a)`	affected	—
`10.3(3r)`	affected	—
`10.3(6)`	affected	—
`9.3(14)`	affected	—
`10.4(4)`	affected	—
`10.3(4h)`	affected	—
`10.5(2)`	affected	—
`10.5(1j)`	affected	—
`8.4(11)`	affected	—
`9.4(3)`	affected	—
`10.3(7)`	affected	—
`10.4(5)`	affected	—
`10.5(3)`	affected	—
`9.3(15)`	affected	—
`9.4(3a)`	affected	—
`10.4(4g)`	affected	—
`10.5(4)`	affected	—
`9.4(3b)`	affected	—
`8.4(12)`	affected	—
`10.6(1)`	affected	—
`10.5(3t)`	affected	—
`10.3(8)`	affected	—
`10.4(6)`	affected	—
`10.5(3s)`	affected	—
`10.5(3e)`	affected	—
`9.4(4)`	affected	—
`10.5(3o)`	affected	—
`9.3(16)`	affected	—
`10.6(1s)`	affected	—
`10.6(2)`	affected	—
`10.5(3p)`	affected	—
`9.4(5)`	affected	—
`10.3(9)`	affected	—
`10.6(2s)`	affected	—
`8.4(13)`	affected	—
`10.6(3)`	affected	—
`10.4(7)`	affected	—
`10.5(5)`	affected	—
`9.3(17)`	affected	—
`10.6(2n)`	affected	—
`10.6(3q)`	affected	—
`10.6(3o)`	affected	—
`10.6(3s)`	affected	—

Cisco

Cisco NX-OS System Software in ACI Mode

unknown

Version	Status	Constraints
`15.2(1g)`	affected	—
`15.2(2e)`	affected	—
`15.2(2f)`	affected	—
`15.2(2g)`	affected	—
`15.2(2h)`	affected	—
`15.2(3f)`	affected	—
`15.2(3e)`	affected	—
`15.2(3g)`	affected	—
`15.2(4d)`	affected	—
`15.2(4e)`	affected	—
`15.2(5c)`	affected	—
`15.2(5d)`	affected	—
`16.0(1g)`	affected	—
`15.2(5e)`	affected	—
`15.2(4f)`	affected	—
`15.2(6e)`	affected	—
`15.2(6h)`	affected	—
`16.0(1j)`	affected	—
`15.2(6g)`	affected	—
`15.2(7f)`	affected	—
`15.2(7g)`	affected	—
`16.0(2h)`	affected	—
`15.2(8d)`	affected	—
`16.0(2j)`	affected	—
`15.2(8e)`	affected	—
`16.0(3d)`	affected	—
`16.0(3e)`	affected	—
`15.2(8f)`	affected	—
`15.2(8g)`	affected	—
`15.3(1d)`	affected	—
`15.2(8h)`	affected	—
`16.0(4c)`	affected	—
`15.3(2a)`	affected	—
`15.2(8i)`	affected	—
`16.0(5h)`	affected	—
`15.3(2b)`	affected	—
`16.0(3g)`	affected	—
`16.0(5j)`	affected	—
`15.3(2c)`	affected	—
`16.0(6c)`	affected	—
`15.3(2d)`	affected	—
`16.1(1f)`	affected	—
`16.0(7e)`	affected	—
`16.0(8e)`	affected	—
`15.3(2e)`	affected	—
`16.0(8f)`	affected	—
`16.1(2f)`	affected	—
`16.1(2g)`	affected	—
`15.3(2f)`	affected	—
`16.0(9c)`	affected	—
`16.1(3f)`	affected	—
`16.0(9d)`	affected	—
`16.0(6h)`	affected	—
`16.0(8h)`	affected	—
`16.1(3g)`	affected	—
`16.0(9e)`	affected	—
`16.1(4h)`	affected	—
`16.1(5e)`	affected	—
`16.2(1g)`	affected	—
`16.0(9f)`	affected	—
`16.2(2e)`	affected	—

Cisco

Cisco Unified Computing System (Managed)

unknown

Version	Status	Constraints
`4.0(1a)`	affected	—
`4.1(1d)`	affected	—
`4.0(4f)`	affected	—
`4.0(4c)`	affected	—
`4.0(2b)`	affected	—
`4.1(2a)`	affected	—
`4.0(4a)`	affected	—
`4.0(4e)`	affected	—
`4.0(4h)`	affected	—
`4.0(2a)`	affected	—
`4.1(1c)`	affected	—
`4.0(1b)`	affected	—
`4.1(1e)`	affected	—
`4.0(4d)`	affected	—
`4.0(4b)`	affected	—
`4.0(2e)`	affected	—
`4.1(1a)`	affected	—
`4.0(4g)`	affected	—
`4.0(1d)`	affected	—
`4.0(1c)`	affected	—
`4.0(4i)`	affected	—
`4.0(2d)`	affected	—
`4.1(1b)`	affected	—
`4.1(2b)`	affected	—
`4.0(4k)`	affected	—
`4.1(3a)`	affected	—
`4.1(3b)`	affected	—
`4.1(2c)`	affected	—
`4.0(4l)`	affected	—
`4.1(4a)`	affected	—
`4.1(3c)`	affected	—
`4.1(3d)`	affected	—
`4.2(1c)`	affected	—
`4.2(1d)`	affected	—
`4.0(4m)`	affected	—
`4.1(3e)`	affected	—
`4.2(1f)`	affected	—
`4.1(3f)`	affected	—
`4.2(1i)`	affected	—
`4.1(3h)`	affected	—
`4.2(1k)`	affected	—
`4.2(1l)`	affected	—
`4.0(4n)`	affected	—
`4.2(1m)`	affected	—
`4.1(3i)`	affected	—
`4.2(2a)`	affected	—
`4.2(1n)`	affected	—
`4.1(3j)`	affected	—
`4.2(2c)`	affected	—
`4.2(2d)`	affected	—
`4.2(3b)`	affected	—
`4.1(3k)`	affected	—
`4.0(4o)`	affected	—
`4.2(2e)`	affected	—
`4.2(3d)`	affected	—
`4.2(3e)`	affected	—
`4.2(3g)`	affected	—
`4.1(3l)`	affected	—
`4.3(2b)`	affected	—
`4.2(3h)`	affected	—
`4.2(3i)`	affected	—
`4.3(2c)`	affected	—
`4.1(3m)`	affected	—
`4.3(2e)`	affected	—
`4.3(3a)`	affected	—
`4.2(3j)`	affected	—
`4.3(3c)`	affected	—
`4.3(4a)`	affected	—
`4.2(3k)`	affected	—
`4.3(4b)`	affected	—
`4.3(4c)`	affected	—
`4.2(3l)`	affected	—
`4.3(4d)`	affected	—
`4.3(2f)`	affected	—
`4.2(3m)`	affected	—
`4.3(5a)`	affected	—
`4.3(4e)`	affected	—
`4.1(3n)`	affected	—
`4.3(4f)`	affected	—
`4.2(3n)`	affected	—
`4.3(5c)`	affected	—
`4.2(3o)`	affected	—
`4.3(5d)`	affected	—
`4.3(6a)`	affected	—
`4.3(6b)`	affected	—
`4.3(5e)`	affected	—
`4.3(6c)`	affected	—
`4.2(3p)`	affected	—
`6.0(1b)`	affected	—
`6.0(1c)`	affected	—
`4.3(6d)`	affected	—
`6.0(1d)`	affected	—
`6.0(1e)`	affected	—
`4.3(6e)`	affected	—
`6.0(1f)`	affected	—
`4.3(6f)`	affected	—
`6.0(2b)`	affected	—
`6.0(1h)`	affected	—
`4.2(3r)`	affected	—
`6.0(2c)`	affected	—
`4.3(6g)`	affected	—
`6.0(2d)`	affected	—
`4.3(6h)`	affected	—
`4.2(3s)`	affected	—
`4.3(6i)`	affected	—

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00282.

Exploitation none

Automatable no

Technical Impact total

References

Link	Providers
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-nxosw1-cWzSbtR

History

Fri, 09 Oct 2026 13:30:00 +0000

Type	Values Removed	Values Added
Metrics	cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}`	cvssV3_1 `{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}`

Wed, 07 Oct 2026 18:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Wed, 07 Oct 2026 16:30:00 +0000

Type	Values Removed	Values Added
Description		As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco NX-OS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76459 are related to out-of-bounds write issues that are grouped under the Common Weakness Enumeration (CWE) CWE-787.
Title		Cisco NX-OS Software Security Hardening Release: October 2026 - Out-of-bounds Write Vulnerabilities
Weaknesses		CWE-787
References		https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-nxosw1-cWzSbtR
Metrics		cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}`

Subscriptions

No data.

MITRE

Status: PUBLISHED

Assigner: cisco

Published: 2026-10-07T16:15:43.747Z

Updated: 2026-10-09T13:07:32.625Z

Reserved: 2026-08-19T12:02:03.637Z

Link: CVE-2026-76459

Vulnrichment

Updated: 2026-10-07T16:50:23.089Z

NVD

Status : Awaiting Analysis

Published: 2026-10-07T17:16:58.553

Modified: 2026-10-09T04:18:12.883

Link: CVE-2026-76459

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-10-07T18:45:12Z

Weaknesses

CWE-787

Tracking

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

Exploitation none

Automatable no

Technical Impact total

Subscriptions

JSON object

JSON object

JSON object

JSON object

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