CVE-2023-20227

HIGH
7.5
CVSS Score
Published: September 27, 2023 at 05:21 PM UTC
Updated: June 17, 2026 at 05:29 AM UTC
41 products affected across 1 vendorIOS Xe4331 Integrated Services Router4431 Integrated Services Router

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Severity
HIGH7.5
Exploit prediction
EPSS 0.9%

Description

A vulnerability in the Layer 2 Tunneling Protocol (L2TP) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of certain L2TP packets. An attacker could exploit this vulnerability by sending crafted L2TP packets to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition. Note: Only traffic directed to the affected system can be used to exploit this vulnerability.

Affected

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

cisco-1000-integrated-services-router (environment) · cisco-1100-4g-integrated-services-router (environment) · cisco-1100-4gltegb-integrated-services-router (environment) · cisco-1100-4gltena-integrated-services-router (environment) · cisco-1100-6g-integrated-services-router (environment) · cisco-4221-integrated-services-router (environment) · cisco-4321-integrated-services-router (environment) · cisco-4321-k9-integrated-services-router (environment) · cisco-4321-k9-rf-integrated-services-router (environment) · cisco-4321-k9-ws-integrated-services-router (environment) · cisco-4331-integrated-services-router (environment) · cisco-4331-k9-integrated-services-router (environment) · cisco-4331-k9-rf-integrated-services-router (environment) · cisco-4331-k9-ws-integrated-services-router (environment) · cisco-4351-integrated-services-router (environment) · cisco-4351-k9-integrated-services-router (environment) · cisco-4351-k9-rf-integrated-services-router (environment) · cisco-4351-k9-ws-integrated-services-router (environment) · cisco-4431-integrated-services-router (environment) · cisco-4451-integrated-services-router (environment) · cisco-4461-integrated-services-router (environment) · cisco-c8200-1n-4t (environment) · cisco-c8200l-1n-4t (environment) · cisco-c8500l-8s4x (environment) · cisco-catalyst-8000v-edge (environment) · cisco-catalyst-8300-1n1s-4t2x (environment) · cisco-catalyst-8300-1n1s-6t (environment) · cisco-catalyst-8300-2n2s-4t2x (environment) · cisco-catalyst-8300-2n2s-6t (environment) · cisco-cloud-services-router-1000v (environment) · cisco-vg400-2fxs-2fxo (environment) · cisco-vg400-4fxs-4fxo (environment) · cisco-vg400-6fxs-6fxo (environment) · cisco-vg400-8fxs (environment) · cisco-vg420-132fxs-6fxo (environment) · cisco-vg420-144fxs (environment) · cisco-vg420-84fxs-6fxo (environment) · cisco-vg450-144fxs-k9 (environment) · cisco-vg450-72fxs-k9 (environment) · cisco-vg450-k9 (environment)

Remediation

No guide yet

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

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-388NVD-CWE-noinfo

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