Cyber Resilience

CVE-2023-28766

Memory Safety in Siemens Siprotec 5 6Md85 Firmware ≤ 9.40

Published
11 April 2023
Modified
11 November 2025
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0094 58th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2023-28766 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Siemens Siprotec 5 6Md85 Firmware. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked in the top 42% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability has been identified in SIPROTEC 5 6MD85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 6MD86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 6MD89 (CP300) (All versions >= V7.80 < V9.64), SIPROTEC 5 6MU85 (CP300)…

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(All versions >= V7.80 < V9.40), SIPROTEC 5 7KE85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SA82 (CP100) (All versions < V8.90), SIPROTEC 5 7SA82 (CP150) (All versions < V9.40), SIPROTEC 5 7SA86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SA87 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SD82 (CP100) (All versions < V8.90), SIPROTEC 5 7SD82 (CP150) (All versions < V9.40), SIPROTEC 5 7SD86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SD87 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SJ81 (CP100) (All versions < V8.89), SIPROTEC 5 7SJ81 (CP150) (All versions < V9.40), SIPROTEC 5 7SJ82 (CP100) (All versions < V8.89), SIPROTEC 5 7SJ82 (CP150) (All versions < V9.40), SIPROTEC 5 7SJ85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SJ86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SK82 (CP100) (All versions < V8.89), SIPROTEC 5 7SK82 (CP150) (All versions < V9.40), SIPROTEC 5 7SK85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SL82 (CP100) (All versions < V8.90), SIPROTEC 5 7SL82 (CP150) (All versions < V9.40), SIPROTEC 5 7SL86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SL87 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SS85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7ST85 (CP300) (All versions >= V7.80 < V9.64), SIPROTEC 5 7ST86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7SX82 (CP150) (All versions < V9.40), SIPROTEC 5 7SX85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7UM85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7UT82 (CP100) (All versions < V8.90), SIPROTEC 5 7UT82 (CP150) (All versions < V9.40), SIPROTEC 5 7UT85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7UT86 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7UT87 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7VE85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7VK87 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 7VU85 (CP300) (All versions >= V7.80 < V9.40), SIPROTEC 5 Communication Module ETH-BA-2EL (Rev.1) (All versions < V9.40 installed on CP150 and CP300 devices), SIPROTEC 5 Communication Module ETH-BA-2EL (Rev.1) (All versions < V8.89 installed on CP100 devices), SIPROTEC 5 Communication Module ETH-BB-2FO (Rev. 1) (All versions < V9.40 installed on CP150 and CP300 devices), SIPROTEC 5 Communication Module ETH-BB-2FO (Rev. 1) (All versions < V8.89 installed on CP100 devices), SIPROTEC 5 Communication Module ETH-BD-2FO (All versions < V9.40), SIPROTEC 5 Compact 7SX800 (CP050) (All versions < V9.40). Affected devices lack proper validation of http request parameters of the hosted web service. An unauthenticated remote attacker could send specially crafted packets that could cause denial of service condition of the target device.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-33121Same vendor: Siemens
CVE-2024-45476Same vendor: Siemens
CVE-2023-38524Same vendor: Siemens
CVE-2024-23799Same vendor: Siemens
CVE-2025-40576Same vendor: Siemens
CVE-2024-23800Same vendor: Siemens
CVE-2023-51744Same vendor: Siemens
CVE-2023-48363Same vendor: Siemens
CVE-2024-22043Same vendor: Siemens
CVE-2024-32637Same vendor: Siemens

Affected Assets

siemens
siprotec 5 6md85 firmware
all versions · ≤ 9.40
siemens
siprotec 5 6md86 firmware
all versions · ≤ 9.40
siemens
siprotec 5 6md89 firmware
all versions
siemens
siprotec 5 6mu85 firmware
≤ 9.40
siemens
siprotec 5 7ke85 firmware
all versions · ≤ 9.40
siemens
siprotec 5 7sa82 firmware
all versions · ≤ 9.40
siemens
siprotec 5 7sa86 firmware
all versions · ≤ 9.40
siemens
siprotec 5 7sa87 firmware
all versions · ≤ 9.40
siemens
siprotec 5 7sd82 firmware
all versions · ≤ 9.40
siemens
siprotec 5 7sd86 firmware
all versions · ≤ 9.40
+29 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References