Security readout for executives and security teams
Plain-English summary
This vulnerability can let an attacker disrupt certain Siemens SIMATIC controllers by sending specially crafted traffic to TCP port 102. The business impact is availability: affected automation devices could be denied service, potentially interrupting industrial processes that depend on them.
Executive priority
Treat as a planned OT remediation item, not an emergency internet-scale issue based on supplied evidence. Prioritize sites where affected controllers support critical operations or TCP/102 is reachable from less trusted networks.
Technical view
CVE-2021-44693 is a CWE-1284 denial-of-service flaw in Siemens SIMATIC controller handling of crafted packets on 102/tcp. CVSS 3.1 is 4.9: network reachable, low attack complexity, high privileges required, no user interaction, no confidentiality or integrity impact, high availability impact.
Likely exposure
Exposure is most likely in operational environments using listed Siemens SIMATIC S7-1200, S7-1500, Drive Controller, or ET 200SP Open Controller versions below the fixed releases, especially where TCP/102 is reachable beyond trusted management paths.
Exploitation context
The supplied sources do not show CISA KEV listing or confirmed active exploitation. CVSS indicates exploitation is possible over the network but requires high privileges and targets availability only.
Researcher notes
Evidence supports denial of service only; no confidentiality or integrity impact is described. The affected list in the bundle is product-specific and should be reconciled against Siemens SSA-382653 before scoping exclusions.
Mitigation direction
- Upgrade affected Siemens devices to the fixed versions listed by Siemens.
- Check Siemens SSA-382653 for product-specific update paths and operational constraints.
- Restrict TCP/102 access to trusted engineering and operations networks.
- Review firewall rules for unnecessary exposure of affected controller interfaces.
- Plan maintenance windows because controller firmware updates can affect operations.
Validation and detection
- Inventory Siemens SIMATIC controllers and record exact model and firmware versions.
- Compare versions against the affected ranges in CVE-2021-44693 and Siemens SSA-382653.
- Confirm TCP/102 reachability from enterprise, remote access, and third-party network paths.
- Verify updated devices report fixed firmware versions after maintenance.
- Monitor operational logs for unexpected controller availability events.
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-1284: 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-2021-44693 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
- Medium
- CVSS
- 4.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
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:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C1.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.9MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://cert-portal.siemens.com/productcert/pdf/ssa-382653.pdfCVE 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.
Improper Validation of Specified Quantity in Input
Improper Validation of Specified Quantity in Input represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.