SB2026100901 - Multiple vulnerabilities in Cisco NX-OS Software

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB2026100901

SB2026100901 - Multiple vulnerabilities in Cisco NX-OS Software

Published: October 9, 2026

Security Bulletin ID SB2026100901
CSH Severity
High
Patch available
YES
Number of vulnerabilities 7
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Critical 14% High 57% Medium 29%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 7 vulnerabilities.


1) Command injection (CVE-ID: CVE-2026-76453)

CWE-ID: CWE-77 - Command injection

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to execute arbitrary commands.

The vulnerability exists due to command injection in Cisco NX-OS Software when commands or arguments are processed without proper neutralization. A remote user can exploit the improper neutralization over the network to execute arbitrary commands.

Affected devices are vulnerable regardless of device configuration.


2) Improper access control (CVE-ID: CVE-2026-76455)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information, modify data, and cause a denial of service.

The vulnerability exists due to improper access control in Cisco NX-OS Software when network-accessible operations are subject to inadequate access restrictions. A remote attacker can bypass access controls over the network to disclose sensitive information, modify data, and cause a denial of service.

Affected devices are vulnerable regardless of device configuration.


3) Input validation error (CVE-ID: CVE-2026-76456)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper input validation in Cisco NX-OS Software when processing special elements used in commands. A remote attacker can exploit the input-validation weakness over the network to cause a denial of service.

Affected devices are vulnerable regardless of device configuration.


4) Out-of-bounds read (CVE-ID: CVE-2026-76457)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to out-of-bounds read issues in Cisco NX-OS Software when memory is read beyond its valid boundaries. A remote attacker can trigger out-of-bounds reads over the network to cause a denial of service.

Affected devices are vulnerable regardless of device configuration.


5) Improper Check or Handling of Exceptional Conditions (CVE-ID: CVE-2026-76458)

CWE-ID: CWE-703 - Improper Check or Handling of Exceptional Conditions

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper handling of exceptional conditions in Cisco NX-OS Software when exceptional conditions arise during network-accessible operations. A remote attacker can trigger improperly handled exceptional conditions over the network to cause a denial of service.

Affected devices are vulnerable regardless of device configuration.


6) Stack-based buffer overflow (CVE-ID: CVE-2026-76459)

CWE-ID: CWE-121 - Stack-based buffer overflow

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information, modify data, and cause a denial of service.

The vulnerability exists due to stack-based buffer overflow issues in Cisco NX-OS Software when writes exceed stack buffer boundaries. A remote user can exploit the buffer overflow over the network to disclose sensitive information, modify data, and cause a denial of service.

Affected devices are vulnerable regardless of device configuration.


7) Heap-based buffer overflow (CVE-ID: CVE-2026-76471)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 10 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H]


The vulnerability allows a remote attacker to execute arbitrary code with root privileges or cause a denial of service.

The vulnerability exists due to a heap-based buffer overflow associated with insufficient input validation in the NX-API feature of Cisco NX-OS Software when processing data sent to the API. A remote attacker can send a crafted HTTP request to the NX-API to execute arbitrary code with root privileges or cause a denial of service.

On Nexus 3000 and 9000 Series Switches, exploitation requires the NX-API feature to be enabled; it is disabled by default. Nexus 9000 Series Switches are affected only in standalone NX-OS mode. On UCS 6300 Series Fabric Interconnects, exploitation requires valid low-privileged user credentials and occurs through the Cisco UCS Manager XML API, which is enabled by default.


Remediation

Install update from vendor's website.

References