Denial of Service Vulnerability in Cisco Nexus Switches
CVE-2025-20241

7.4HIGH

Key Information:

Vendor

Cisco
Status
Cisco Nx-os Software
Vendor
CVE Published:
27 August 2025

Badges

👾 Exploit Exists

What is CVE-2025-20241?

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) feature of Cisco Nexus 3000 and 9000 Series Switches can enable an unauthenticated, adjacent attacker to force the IS-IS process to restart unexpectedly, potentially leading to a disruption in service. This issue arises from inadequate input validation during IS-IS packet processing. An attacker positioned on Layer 2 adjacent to the device can exploit this by sending a specially crafted IS-IS packet, which may trigger an unexpected restart of the IS-IS process and result in a device reload, instigating a denial of service condition.

Affected Version(s)

Cisco NX-OS Software 9.2(3)

Cisco NX-OS Software 7.0(3)I5(2)

Cisco NX-OS Software 6.0(2)A8(7a)

References

https://sec.cloudapps.cisco.com/security/center/content/C...

CVSS V3.1

Score:
7.4
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Changed

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

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CVE-2025-20241 : Denial of Service Vulnerability in Cisco Nexus Switches