The MA-L block 48:81:4E is registered to E&M SOLUTION CO,.Ltd (이앤엠솔루션 주식회사), a South Korean manufacturer of network video surveillance infrastructure based in Ansan-si, Gyeonggi-do. As an MA-L (full 24-bit OUI) assignment it covers the entire range 48:81:4E:00:00:00 through 48:81:4E:FF:FF:FF, roughly 16.7M addresses. The company builds Linux-based PC NVRs (network video recorders), VMS platforms, network video servers, and central monitoring stations under the REDBACK and ENM product lines — for example the ENM-N81B24H is an 81-channel Linux PC NVR, and the ENM-NDS series covers compact network video servers. These are enterprise CCTV/IP-camera appliances that are network-connected and frequently remotely accessible, which is the relevant context when one shows up on a network: confirm it is intentional, keep it off the public internet, and keep firmware and credentials current. No vendor-specific CVEs were found for E&M Solution products, but that absence is low-signal for a smaller vendor — the NVR/VMS device class as a whole is actively targeted (Mirai-family botnets, unauthenticated RCE), so the class-level risk applies regardless. IEEE publishes no registration date for OUI blocks, so no allocation date is recorded here; the "December 1, 2022" value seen in third-party lookup databases is a scrape artifact, not an IEEE fact.
- IEEE assignment
- 48:81:4E → E&M SOLUTION CO,.Ltd, MA-L block [Confirmed] — enrichment/registries/oui.csv (line 332); IEEE MA-L
- Registry / block size
- MA-L (24-bit OUI), covers 48:81:4E:00:00:00–48:81:4E:FF:FF:FF (~16.7M addresses) [Confirmed] — IEEE MA-L; https://api.maclookup.app/v2/macs/48:81:4E. NOTE: IEEE public OUI data publishes NO assignment/registration date; the "2022-12-01" value on maclookup.app is a third-party database artifact, not an IEEE fact, and is NOT recorded as a registration date here.
- Organization
- E&M SOLUTION CO,.Ltd (이앤엠솔루션 주식회사) [Confirmed] — enrichment/registries/oui.csv; https://en.enmsolution.com/; https://api.maclookup.app/v2/macs/48:81:4E
- HQ / country
- #813-ho, 555, Byeolmang-ro, Danwon-gu, Ansan-si, Gyeonggi-do 15434, South Korea (KR) [Confirmed] — enrichment/registries/oui.csv; https://www.macvendorlookup.com/api/v2/48:81:4E; https://en.enmsolution.com/
- Company status
- active [Confirmed] — https://en.enmsolution.com/
- Device types
- Network Video Recorders (Linux PC NVR), VMS platforms (REDBACK VMS), network video/display servers (EM-NTS, ENM-NDS-04, ENM-NDS-SOLO), data archive systems (REDBACK DAS), central monitoring stations (EM-CMS Station H), compact server appliances (1U B2 Essential) [Confirmed] — https://en.enmsolution.com/; https://enmsolution.com/product/enm-nds-04-...
- Notable products
- ENM-N81B24H (81-channel Linux PC NVR), REDBACK VMS/DAS series, ENM-NDS network video servers [Confirmed] — https://enmsolution.com/product/enm-n81b24h-...
- Corporate details
- CEO 김은미 (Kim Eun-mi); South Korea business registration number 553-81-01730 [Likely] — https://en.enmsolution.com/ (single-source vendor site)
- Website
- https://en.enmsolution.com/ (English), https://enmsolution.com/ (Korean) [Confirmed] — https://en.enmsolution.com/
- Allocated date
- Unknown — IEEE publishes no OUI registration dates; not fabricated [Unknown] — IEEE MA-L
- Security context
- No published CVEs or advisories for E&M Solution / ENM products specifically; absence is low-signal for a smaller vendor. The broader NVR/VMS class (network-connected, Linux-based, remotely accessible) is actively targeted by Mirai-family botnets via default credentials and unauthenticated RCE, and CISA has flagged NVR classes generically (e.g. ICSA-24-025-02; CVE-2024-39950). Treat any such device as a managed asset: keep off the public internet, patch firmware, change defaults. [Likely] — https://www.cisa.gov/news-events/ics-advisories/icsa-24-025-02; https://nvd.nist.gov/vuln/detail/CVE-2024-39950
- Analyst note
- A 48:81:4E address reliably identifies E&M Solution surveillance hardware; given the device class, its presence on a network warrants verification that it is intentional and properly segmented.