CVE intelligence and bounded remediation

CVE-2021-25666 — A vulnerability has been identified in SCALANCE W780 and W740 (IEEE 802.11n) family (All versions < V6.3)

Medium CVSS 4.3

A vulnerability has been identified in SCALANCE W780 and W740 (IEEE 802.11n) family (All versions < V6.3). Sending specially crafted packets through the ARP protocol to an affected device could cause a partial denial-of-service, preventing the device to operate normally for a short period of time.

Severity
Medium
CVSS
4.3 (3.1)
Published
2021-02-09
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-770

Affected products

  • siemens / scalance_w780_firmware
  • siemens / scalance_w740_firmware

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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