CVE-2019-12652

Cisco Catalyst 4000 Series Switches TCP Denial of Service Vulnerability

HIGH
7.5
CVSS Score
Published: September 25, 2019 at 08:16 PM UTC
Updated: June 17, 2026 at 02:15 AM UTC
6 products affected across 1 vendorIOSCatalyst 4500 Supervisor Engine 6-ECatalyst 4900M

Using Cisco IOS 15.0(1)XO1 by Cisco?

Get instant alerts when new vulnerabilities affect Cisco IOS 15.0(1)XO1 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.5
Exploit prediction
EPSS 3%
SSVC
No known exploit

Description

A vulnerability in the ingress packet processing function of Cisco IOS Software for Cisco Catalyst 4000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource allocation when processing TCP packets directed to the device on specific Cisco Catalyst 4000 Series Switches. An attacker could exploit this vulnerability by sending crafted TCP streams to an affected device. A successful exploit could cause the affected device to run out of buffer resources, impairing operations of control plane and management plane protocols, resulting in a DoS condition. This vulnerability can be triggered only by traffic that is destined to an affected device and cannot be exploited using traffic that transits an affected device.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

cisco-catalyst-4500-supervisor-engine-6-e (environment) · cisco-catalyst-4500-supervisor-engine-6l-e (environment) · cisco-catalyst-4900m (environment) · cisco-catalyst-4948e (environment) · cisco-catalyst-4948e-f (environment)
All versions
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-399NVD-CWE-Other

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card