CVE intelligence and bounded remediation

CVE-2024-20434 — Cisco Ios Xe security vulnerability

Medium CVSS 4.3

A vulnerability in Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the control plane of an affected device. This vulnerability is due to improper handling of frames with VLAN tag information. An attacker could exploit this vulnerability by sending crafted frames to an affected device. A successful exploit could allow the attacker to render the control plane of the affected device unresponsive. The device would not be accessible through the console or CLI, and it would not respond to ping requests, SNMP requests, or requests from other control plane protocols. Traffic that is traversing the device through the data plane is not affected. A reload of the device is required to restore control plane services.

Severity
Medium
CVSS
4.3 (3.1)
Published
2024-09-25
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-190

Affected products

  • cisco / ios_xe / 16.6.1
  • cisco / ios_xe / 16.6.2
  • cisco / ios_xe / 16.6.3
  • cisco / ios_xe / 16.6.4
  • cisco / ios_xe / 16.6.4a
  • cisco / ios_xe / 16.6.5

Showing 6 representative product identities from 91 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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