CVE intelligence and bounded remediation

CVE-2021-25674 — A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions)

Medium CVSS 5.5

A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions). An attacker with local access to the system could cause a Denial-of-Service condition in the application when it is used to open a specially crafted file. As a consequence, a NULL pointer deference condition could cause the application to terminate unexpectedly and must be restarted to restore the service.

Severity
Medium
CVSS
5.5 (3.1)
Published
2021-03-15
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-476

Affected products

  • siemens / simatic_s7-plcsim / 5.4

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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