Cpu 1504d Tf FirmwareOperating system · Siemens

CVE-2020-28397

MEDIUM · 5.3 CVSS v3.1 Published 2021-08-10
Fix available
A fix is available. Upgrade to 2.9.2 / 4.0 or later.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability has been identified in SIMATIC Drive Controller family (All versions < V2.9.2), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions < V21.9), SIMATIC S7 PLCSIM Advanced (All versions > V2 < V4), SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (Version V4.4), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions > V2.5 < V2.9.2), SIMATIC S7-1500 Software Controller (All versions > V2.5 < V21.9), TIM 1531 IRC (incl. SIPLUS NET variants) (Version V2.1). Due to an incorrect authorization check in the affected component, an attacker could extract information about access protected PLC program variables over port 102/tcp from an affected device when reading multiple attributes at once.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-863

An authorization check exists but is flawed, so it passes when it should fail. Attackers probe roles and object references to find the gap. Remediation means centralising and correctly implementing the access-control logic, then testing it against every role.

General guidance for the incorrect authorization class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Cpu 1504d Tf FirmwareOperating system
Affected:< 2.9.2
Cpu 1507d Tf FirmwareOperating system
Affected:< 2.9.2
Cpu 1515sp Pc2 Tf FirmwareOperating system
Affected:< 21.9
Simatic S7 Plcsim Advanced FirmwareOperating system
Affected:>= 2.0, < 4.0
Simatic S7 1500 Software ControllerApplication
Affected:>= 2.5, < 21.9
Tim 1531 Irc FirmwareOperating system
Affected:= 2.1
Cpu 1211c FirmwareOperating system
Affected:= 4.4
Cpu 1212c FirmwareOperating system
Affected:= 4.4

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to 2.9.2 / 4.0 / 21.9 or later
Fixed in 2.9.24.021.9
We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-28397 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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