Security readout for executives and security teams
Plain-English summary
This flaw can let a remote, unauthenticated attacker crash the OPC Foundation Local Discovery Server by sending malformed messages. The main business impact is availability: discovery services in industrial environments may become unavailable, disrupting visibility or connection workflows rather than exposing data.
Executive priority
Treat this as a high-priority availability risk for OT and industrial systems using OPC UA discovery. It is less about data theft and more about preventable service disruption. Patch or contain affected LDS deployments after confirming operational dependencies.
Technical view
CVE-2021-40142 affects OPC Foundation Local Discovery Server before 1.04.402.463. The CVE describes access past the end of a buffer caused by crafted messages, leading to denial of service. CVSS 3.1 is 7.5 with network attack vector, low complexity, no privileges, no user interaction, and availability impact only.
Likely exposure
Exposure is likely limited to environments running OPC Foundation LDS versions before 1.04.402.463. The provided affected-product metadata is incomplete, so teams should inventory OPC UA discovery services and check vendor advisories for embedded or redistributed LDS components.
Exploitation context
The source bundle does not identify active exploitation, and KEV status is false. The CVSS vector indicates unauthenticated network reachability and low attack complexity, but only denial-of-service impact is supported by the provided evidence.
Researcher notes
The provided CVE data lacks precise affected CPEs and CWE entries. Analysis is based on the CVE description, CVSS vector, OPC Foundation references, and Siemens confirmation reference. Do not infer broader product impact without the vendor advisories.
Mitigation direction
- Upgrade OPC Foundation LDS to 1.04.402.463 or later where deployed.
- Review OPC Foundation and Siemens advisories for product-specific guidance.
- Restrict LDS network access to trusted OPC UA hosts only.
- Monitor LDS crashes, restarts, and availability alarms.
- Prioritize OT sites where LDS downtime affects operations.
Validation and detection
- Inventory hosts running OPC Foundation Local Discovery Server.
- Confirm installed LDS versions are 1.04.402.463 or later.
- Check Siemens advisory applicability for vendor-packaged deployments.
- Review firewall rules controlling access to LDS endpoints.
- Correlate service crashes with unexpected remote connection attempts.
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.
CVE-2021-40142 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
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:N/S:U/UI: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:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:N/S:U/UI:N3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:N/S:U/UI:N
Source materials
- CVE List V5 sourceCVE List V5
- https://opcfoundation.org/security-bulletins/CVE reference · x_refsource_MISC
- https://files.opcfoundation.org/SecurityBulletins/OPC%20Foundation%20Security%20Bulletin%20CVE-2021-40142.pdfCVE reference · x_refsource_MISC
- https://cert-portal.siemens.com/productcert/pdf/ssa-321292.pdfCVE reference · x_refsource_CONFIRM
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.