CVE intelligence and bounded remediation

CVE-2022-20854 — Cisco Secure Firewall Management Center security vulnerability

High CVSS 7.5

A vulnerability in the processing of SSH connections of Cisco Firepower Management Center (FMC) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a reboot on the affected device.

Severity
High
CVSS
7.5 (3.1)
Published
2022-11-15
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-400, CWE-755

Affected products

  • cisco / secure_firewall_management_center
  • cisco / secure_firewall_management_center / 6.2.1
  • cisco / secure_firewall_management_center / 6.6.0
  • cisco / secure_firewall_management_center / 6.6.0.1
  • cisco / secure_firewall_management_center / 6.6.1

Showing 5 representative product identities from 50 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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