In SIMATIC MV400 family versions prior to v7.0.6, the ISN generator is initialized with a…
Priority LOW 37Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
In SIMATIC MV400 family versions prior to v7.0.6, the ISN generator is initialized with a constant value and has constant increments. An attacker could predict and hijack TCP sessions.
Why it matters now
EPSS 0.02139 82nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:siemens:simatic_mv420_firmware:*:*:*:*:*:*:*:* | before 7.0.6 | Vulnerable | Siemens |
| cpe:2.3:h:siemens:simatic_mv420:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
| cpe:2.3:o:siemens:simatic_mv440_firmware:*:*:*:*:*:*:*:* | before 7.0.6 | Vulnerable | Siemens |
| cpe:2.3:h:siemens:simatic_mv440:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
- cpe:2.3:o:siemens:simatic_mv420_firmware:*:*:*:*:*:*:*:* Versions before 7.0.6 Vulnerable ·Siemens
- cpe:2.3:h:siemens:simatic_mv420:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
- cpe:2.3:o:siemens:simatic_mv440_firmware:*:*:*:*:*:*:*:* Versions before 7.0.6 Vulnerable ·Siemens
- cpe:2.3:h:siemens:simatic_mv440:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-27632
- 2026-10-03 Alias added: GHSA-53pq-r3c7-x97x
References
More Siemens Simatic Mv420 Firmware vulnerabilities
- TI-2019-10399 Uncontrolled resource consumption in Siemens Development/Evaluation Kits for PROFINET IO… CVSS 3.1HIGH 7.5
- TI-2019-08146 Improper access control in Siemens SIMATIC MV400 family CVSS 3.1HIGH 7.1
- TI-2019-08147 Cleartext transmission of sensitive information in Siemens SIMATIC MV400 family CVSS 3.0MEDIUM 5.3
Sources
- CVE-2020-27632 · CVE Program
- CVE-2020-27632 · NVD
- FIRST EPSS
- GHSA-53pq-r3c7-x97x · GitHub Advisory Database · CC BY 4.0
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