CVE intelligence and bounded remediation

CVE-2023-20033 — Cisco Ios Xe security vulnerability

High CVSS 8.6

A vulnerability in Cisco IOS XE Software for Cisco Catalyst 3650 and Catalyst 3850 Series Switches could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper resource management when processing traffic that is received on the management interface. An attacker could exploit this vulnerability by sending a high rate of traffic to the management interface. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Severity
High
CVSS
8.6 (3.1)
Published
2023-09-27
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-770

Affected products

  • cisco / ios_xe / 16.3.1
  • cisco / ios_xe / 16.3.1a
  • cisco / ios_xe / 16.3.2
  • cisco / ios_xe / 16.3.3
  • cisco / ios_xe / 16.3.4
  • cisco / ios_xe / 16.3.5

Showing 6 representative product identities from 58 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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