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Mallory
Critical

Code Injection via Unsanitized Trace File Import in Siemens SIMATIC Devices

IdentifiersCVE-2025-40943CWE-74

CVE-2025-40943 affects multiple Siemens SIMATIC products, including SIMATIC Drive Controller CPU 1504D TF and 1507D TF, multiple SIMATIC ET 200SP CPU variants, SIMATIC ET 200SP Open Controller CPU 1515SP PC/PC2/PC3 variants, and SIMATIC S7-1500 devices. The vulnerability is caused by improper sanitization of the contents of trace files during import. A remote attacker can craft a malicious trace file containing injected code and, through social engineering, induce a legitimate user to import that file into an affected device or engineering environment. Successful exploitation results in code injection in the context of the trace file handling functionality.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows an attacker to inject code by abusing the trace file import mechanism. Based on the provided information, this can compromise the integrity of the affected system or associated engineering workflow and may enable execution of attacker-controlled content in the context of the importing user or application. The attack requires user-assisted import of a specially crafted file rather than unauthenticated direct network exploitation.

Mitigation

If you can’t patch tonight, do this now.

Do not import trace files from untrusted or unauthenticated sources. Restrict who can provide trace files to operators and engineers, and validate file provenance before import. Reduce exposure to social engineering by training users who handle diagnostic or trace data. Where operationally feasible, perform trace file handling only on trusted workstations and within controlled administrative workflows until vendor fixes are applied.

Remediation

Patch, then assume compromise.

Apply the Siemens security updates referenced in the March 10, 2026 Siemens advisories, including SSA-452276, SSA-903736, and SSB-751527, as applicable to the affected product and version. The provided content indicates that some affected product lines are vulnerable in all versions, while others are affected only in versions prior to 4.1.2; upgrade to fixed versions identified by Siemens for each specific model.
PUBLIC EXPLOITS

Exploits

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

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Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity3

Community discussion across Reddit, Mastodon, and other social sources.