Western Digital — 4 confirmed MA-L blocks (HGST family)

Western Digital Corporation (NASDAQ: WDC) holds four confirmed IEEE MA-L (24-bit OUI) assignments spread across three distinct registered entity-name/address variants, which together corroborate a real, operating storage manufacturer rather than a single-block shell registration: 00:00:C0 under "WESTERN DIGITAL CORPORATION" (Irvine, CA), 00:90:A9 under "WESTERN DIGITAL" (Rochester, MN), 00:0C:CA under "HGST a Western Digital Company" (San Jose, CA — reflecting WD's acquisition of Hitachi Global Storage Technologies), and 00:14:EE under "Western Digital Technologies, Inc." (Lake Forest, CA). No MA-M or MA-S blocks were found for Western Digital or HGST in the cached IEEE mid-size/small registries. A fifth possible block, CA:08:3C, surfaces only in Wireshark's third-party the Wireshark manufacturer database and is not present in the cached IEEE the IEEE MA-L registry snapshot used here, so it is recorded as an unresolved discrepancy rather than a confirmed fifth assignment. Network-connected hardware bearing these OUIs centers on Western Digital's My Cloud network-attached storage line, which carries a substantial, independently verifiable public security history — most recently CVE-2025-30247, a critical unauthenticated remote-code-execution flaw patched in September 2025.

IEEE MA-L assignments

00:00:C0 → "WESTERN DIGITAL CORPORATION", 8105 Irvine Center Drive, Irvine, CA 92718, US; 00:90:A9 → "WESTERN DIGITAL", 1599 North Broadway, Rochester, MN 55906, US; 00:0C:CA → "HGST a Western Digital Company", 3403 Yerba Buena Road, San Jose, CA 95135, US; 00:14:EE → "Western Digital Technologies, Inc.", 20511 Lake Forest Dr., Lake Forest, CA 92630, US [Confirmed — corroborated by both R1-registry and W1-web independently] — https://standards-oui.ieee.org/oui/oui.csv

Registry / block size

MA-L (24-bit OUI) for all 4 confirmed blocks; no matching MA-M (the IEEE MA-S registry) or MA-S (the IEEE MA-M registry) blocks found for Western Digital or HGST [Confirmed] — the IEEE MA-L registry, the IEEE MA-S registry, the IEEE MA-M registry

Possible 5th block (unresolved)

CA:08:3C → "Western Digital Technologies, Inc." per Wireshark's the Wireshark manufacturer database only; absent from the cached IEEE the IEEE MA-L registry used in this pass. Not counted as a confirmed assignment pending re-verification against the live IEEE registry. [Unknown — single-source, third-party derived file] — the Wireshark manufacturer database (line 50962)

Registration dates

unknown for all blocks — IEEE's public OUI registry (the IEEE MA-L registry) publishes no assignment/registration-date field for MA-L records; no date inferred or fabricated. Any third-party "date registered" would be a database artifact of that tool's own record-creation time, not an IEEE fact.

[Confirmed absence] — https://standards-oui.ieee.org/oui/oui.csv

IANA reference

not applicable / blank — IANA references apply to protocol registries, not IEEE OUI/MAC vendor assignments [Confirmed] — n/a

Company / website

Western Digital Corporation, publicly traded (NASDAQ: WDC), data-storage manufacturer headquartered in San Jose, CA; ships external/internal HDDs, SSDs, and NAS under the WD, My Cloud, My Passport, and G-Drive brands [Confirmed] — https://www.westerndigital.com/company

Device types

network-attached storage (My Cloud, My Cloud EX2/EX4/PR2100/PR4100/DL2100/DL4100/Mirror Gen 2 families) and enterprise/consumer internal & external HDD/SSD hardware [Confirmed] — https://www.westerndigital.com/company, https://www.helpnetsecurity.com/2025/09/30/western-digital-my-cloud-nas-cve-2025-30247/

Security context

CVE-2025-30247, a critical (CVSS 9.4) unauthenticated OS command-injection vulnerability in My Cloud firmware prior to v5.31.108, fixed September 23, 2025, affecting the My Cloud PR2100/PR4100/EX2 Ultra/EX4100/Mirror Gen 2/EX2100/DL2100/DL4100 and base My Cloud units [Confirmed] — https://www.helpnetsecurity.com/2025/09/30/western-digital-my-cloud-nas-cve-2025-30247/, https://cyberinsider.com/western-digital-fixes-critical-remote-code-execution-flaw-in-my-cloud-nas-devices/. Earlier 2021 My Book Live mass remote-wipe incident is well known but not independently re-verified this pass [Likely]

Related vendors

HGST / Hitachi Global Storage Technologies (Western Digital subsidiary/brand, consistent with the 00:0C:CA registrant string) [Confirmed] — IEEE MA-L

Company substance assessment

substantive — 4 independent confirmed IEEE MA-L assignments across 3 distinct registered entity-name/address variants, an identifiable and corroborated product line (My Cloud NAS, WD Red/Blue/Black, HGST enterprise storage), and an extensive independently-verifiable public CVE/security-advisory history tied to network-connected devices bearing these OUIs [Confirmed]