CVE intelligence and bounded remediation

CVE-2016-6439 — Cisco Secure Firewall Management Center security vulnerability

High CVSS 7.5

A vulnerability in the detection engine reassembly of HTTP packets for Cisco Firepower System Software before 6.0.1 could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the Snort process unexpectedly restarting. The vulnerability is due to improper handling of an HTTP packet stream. An attacker could exploit this vulnerability by sending a crafted HTTP packet stream to the detection engine on the targeted device. An exploit could allow the attacker to cause a DoS condition if the Snort process restarts and traffic inspection is bypassed or traffic is dropped.

Severity
High
CVSS
7.5 (3.0)
Published
2016-10-27
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-399

Affected products

  • cisco / secure_firewall_management_center / 5.3.0
  • cisco / secure_firewall_management_center / 5.3.0.2
  • cisco / secure_firewall_management_center / 5.3.0.3
  • cisco / secure_firewall_management_center / 5.3.0.4
  • cisco / secure_firewall_management_center / 5.3.1
  • cisco / secure_firewall_management_center / 5.3.1.3

Showing 6 representative product identities from 24 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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