Security readout for executives and security teams
Plain-English summary
This CVE describes a denial-of-service weakness in STMicroelectronics STM32Cube Middleware v1.8.0 and below. Affected embedded systems may stop functioning correctly when communicating with a connected USB endpoint. The public bundle does not provide CVSS, a CWE, confirmed affected products, or a named fixed version.
Executive priority
Prioritize assessment for products that expose USB host ports in customer, field, or unattended environments. Business urgency is unclear without CVSS, affected product mapping, or vendor remediation detail, but denial of service may matter for safety, availability, or support-sensitive devices.
Technical view
The issue is reported in USBH_MSC_InterfaceInit(), part of the USB Mass Storage host path. The CVE states that communication with a connected endpoint can trigger denial of service. Available source data is sparse and does not describe root cause, exploit reliability, impact scope, or remediation specifics.
Likely exposure
Exposure is most plausible in embedded firmware that includes STM32Cube Middleware v1.8.0 or below and enables USB host Mass Storage functionality. The bundle does not identify downstream products, CPEs, or specific deployed device families.
Exploitation context
CISA KEV is false in the provided bundle, and no cited source confirms active exploitation. The described trigger involves communication with a connected USB endpoint, so validation should focus on systems where untrusted or field-accessible USB devices can interact with firmware.
Researcher notes
The record is under-specified: affected vendor/product fields are n/a, severity is unknown, and no CWE is listed. Avoid broad product claims. Focus research on STM32Cube Middleware versioning, USB Mass Storage host usage, and the linked STM32CubeH7 issue for implementation context.
Mitigation direction
- Inventory firmware builds using STM32Cube Middleware v1.8.0 or below.
- Review STMicroelectronics guidance and the linked issue for fixed middleware or patches.
- Disable USB Mass Storage host support where it is not operationally required.
- Restrict access to physical USB ports on deployed devices.
- Treat untrusted USB endpoints as denial-of-service risk until assessed.
Validation and detection
- Confirm whether USBH_MSC_InterfaceInit() exists in the firmware source tree.
- Check middleware version metadata against v1.8.0 and below.
- Determine whether USB host Mass Storage is compiled and reachable.
- Review product threat models for untrusted USB endpoint access.
- Document any vendor advisory, patch, or compensating control found.
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-2021-34267 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/STMicroelectronics/STM32CubeH7/issues/80CVE reference · x_refsource_MISC
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.