CVE intelligence and bounded remediation

CVE-2020-3426 — Cisco Ios security vulnerability

Critical CVSS 9.1

A vulnerability in the implementation of the Low Power, Wide Area (LPWA) subsystem of Cisco IOS Software for Cisco 800 Series Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an unauthenticated, remote attacker to gain unauthorized read access to sensitive data or cause a denial of service (DoS) condition. The vulnerability is due to a lack of input and validation checking mechanisms for virtual-LPWA (VLPWA) protocol modem messages. An attacker could exploit this vulnerability by supplying crafted packets to an affected device. A successful exploit could allow the attacker to gain unauthorized read access to sensitive data or cause the VLPWA interface of the affected device to shut down, resulting in DoS condition.

Severity
Critical
CVSS
9.1 (3.1)
Published
2020-09-24
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-264, CWE-20

Affected products

  • cisco / ios

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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