Microsoft
Disclosed Jan 19, 20242 years agoConfirmed
Russian state hackers access Microsoft senior leadership email accounts
Microsoft detected on January 12, 2024 that the Russia-linked group Midnight Blizzard had accessed and exfiltrated data from a small percentage of corporate email accounts, including senior leadership, since late November 2023. In a March 2024 amended filing Microsoft said the actor used the stolen information to try to access source code repositories and internal systems.
What is known
| People affected | Not stated in the sources we have |
|---|---|
| Disclosed | Jan 19, 2024 |
| Discovered | Jan 12, 2024 |
| Attack | Hacking |
| Data exposed | Emails, Messages, Internal documents, Source code |
| Sector | Tech · US |
| Status | Confirmed |
Sources
| Source | |
|---|---|
| Microsoft Corp Form 8-K, Item 1.05 (2024-01-19)sec.gov · SEC filing | SEC filing |
| Microsoft Corp Form 8-K/A, Item 1.05 (2024-03-08)sec.gov · SEC filing | SEC filing |
| US says Russian hackers stole federal government emails during Microsoft cyberattacktechcrunch.com · News | News |
Notices filed
Other breaches at Microsoft
History of this record
- 2026-09-25 · attack: unknown to hacking · seed source
- 2026-09-25 · data_types: [] to ["emails","messages","internal-docs","source-code"] · seed source
- 2026-09-25 · discovered: empty to 2024-01-12 · seed source
- 2026-09-25 · summary: empty to Microsoft detected on January 12, 2024 that the Russia-linked group Midnight Blizzard had accessed and exfiltrated data from a small percentage of corporate email accounts, including senior leadership, since late November 2023. In a March 2 · seed source
- 2026-09-25 · title: Material cybersecurity incident reported to the SEC (8-K Item 1.05) to Russian state hackers access Microsoft senior leadership email accounts · seed source
- 2026-09-25 · added · backfill source
First seen 2026-09-25 (SEC 8-K), confirmed by SEC 8-K. Record counts are as reported. Not legal advice.