CVE intelligence and bounded remediation

CVE-2017-3820 — Cisco Ios Xe security vulnerability

Medium CVSS 6.8

A vulnerability in Simple Network Management Protocol (SNMP) functions of Cisco ASR 1000 Series Aggregation Services Routers running Cisco IOS XE Software Release 3.13.6S, 3.16.2S, or 3.17.1S could allow an authenticated, remote attacker to cause high CPU usage on an affected device, resulting in a denial of service (DoS) condition. More Information: CSCux68796. Known Affected Releases: 15.5(3)S2.1 15.6(1)S1.1. Known Fixed Releases: 15.4(3)S6.1 15.4(3)S6.2 15.5(3)S2.2 15.5(3)S3 15.6(0.22)S0.23 15.6(1)S2 16.2(0.295) 16.3(0.94) 15.5.3S3.

Severity
Medium
CVSS
6.8 (2.0)
Published
2017-02-03
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-665

Affected products

  • cisco / ios_xe / 3.13.6s
  • cisco / ios_xe / 3.16.2s
  • cisco / ios_xe / 3.17.1s

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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