Security readout for executives and security teams
Plain-English summary
This Siemens industrial networking vulnerability can let an unauthenticated network attacker make affected devices unavailable by overwhelming them with PROFINET DCP reset traffic. The main business risk is loss or disruption of network connectivity for industrial operations that depend on affected Siemens SCALANCE, RUGGEDCOM, or PROFINET development/evaluation devices.
Executive priority
Treat as high priority for environments where affected Siemens devices support production, remote connectivity, or OT availability. It is not currently KEV-listed in the provided bundle, but the unauthenticated network attack path and availability impact justify prompt inventory and vendor-guided remediation.
Technical view
CVE-2020-28400 is a network-reachable denial-of-service issue in affected Siemens devices. The source describes CWE-770 resource allocation weakness: large volumes of DCP reset packets can trigger device unavailability. CVSS v4.0 is 8.7 with no privileges or user interaction required and high vulnerable-system availability impact.
Likely exposure
Exposure is most likely in OT or industrial networks using the listed Siemens PROFINET IO development/evaluation kits, RUGGEDCOM RM1224 LTE variants, SCALANCE M routers, or SCALANCE MUM853-1. Version detail in the bundle is incomplete, so asset owners should confirm exact affected versions from Siemens SSA-599968.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. The described attack is unauthenticated and network-based, but exploitation requires network reachability to affected devices and enough traffic to create the denial-of-service condition.
Researcher notes
Evidence is sufficient for a DoS assessment but incomplete for precise fixed versions or patches. The affected list contains repeated entries and version value “0,” so researchers should normalize affected products against Siemens SSA-599968 before exposure reporting or scanner logic.
Mitigation direction
- Review Siemens SSA-599968 for product-specific updates, fixed versions, and mitigations.
- Review CISA ICSA-21-194-03 for operational guidance before changes in OT environments.
- Restrict access to affected device management and PROFINET networks to trusted hosts only.
- Apply compensating monitoring and segmentation where vendor remediation is unavailable or delayed.
- Plan remediation during maintenance windows because availability-impacting devices may support operations.
Validation and detection
- Inventory Siemens products against the affected list in the CVE bundle and Siemens advisory.
- Confirm firmware or product version status using Siemens SSA-599968, not the incomplete bundle version value.
- Review network architecture for untrusted reachability to affected PROFINET or router segments.
- Check operational logs for unexplained resets, outages, or availability drops around affected devices.
- Avoid production flood testing; validate controls through approved lab or change-management processes.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-770: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-28400 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.7 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
8.7HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- https://cert-portal.siemens.com/productcert/pdf/ssa-599968.pdfCVE reference · x_refsource_MISC
- https://us-cert.cisa.gov/ics/advisories/icsa-21-194-03CVE reference · x_refsource_MISC
- https://cert-portal.siemens.com/productcert/html/ssa-599968.htmlCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Allocation of Resources Without Limits or Throttling
Allocation of Resources Without Limits or Throttling represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.