CVE intelligence and bounded remediation

CVE-2020-3390 — Cisco Ios Xe security vulnerability

High CVSS 7.4

A vulnerability in Simple Network Management Protocol (SNMP) trap generation for wireless clients of the Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause the device to unexpectedly reload, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to the lack of input validation of the information used to generate an SNMP trap in relation to a wireless client connection. An attacker could exploit this vulnerability by sending an 802.1x packet with crafted parameters during the wireless authentication setup phase of a connection. A successful exploit could allow the attacker to cause the device to reload, causing a DoS condition.

Severity
High
CVSS
7.4 (3.1)
Published
2020-09-24
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-20

Affected products

  • cisco / ios_xe / 16.12.1

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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