---
title: "Microsoft security incident"
description: "What the retained public evidence establishes about the Microsoft incident, its attack path, impact, and response."
incident_type: "Cybersecurity incident"
status: "active"
last_modified: "2026-09-19"
canonical_url: "https://www.ally.security/incidents/microsoft-security-incident-2022"
markdown_url: "https://www.ally.security/incidents/microsoft-security-incident-2022.md"
stix_url: "https://www.ally.security/incidents/microsoft-security-incident-2022/stix.json"
---

# Microsoft security incident

Lapsus$; single compromised employee account. Partial source code for Bing/Cortana and other products accessed.

Last modified Sep 19, 2026 · 1 source

## Summary

- **Environment:** Tech
- **Operational impact:** Partial source code for Bing/Cortana and other products accessed
- **Financial impact:** No financial figure is established by the reviewed source evidence

## What happened

In 2022, Microsoft experienced an incident in its tech environment. The retained source describes the attack path as follows: Lapsus$; single compromised employee account. [1](#source-1)

The documented consequence was: Partial source code for Bing/Cortana and other products accessed. [1](#source-1)

## Impact

- Documented impact: Partial source code for Bing/Cortana and other products accessed. [1](#source-1)
- No financial loss, ransom amount, recovery cost, or regulatory penalty is established by the reviewed source evidence.

## Timeline

### March 22, 2022 — Documented public update

The [DEV-0537 criminal actor targeting organizations](https://www.microsoft.com/security/blog/2022/03/22/dev-0537-criminal-actor-targeting-organizations-for-data-exfiltration-and-destruction/) records the incident facts used in this briefing. [1](#source-1)

### September 19, 2026 — Briefing updated

This briefing was last reviewed and updated on September 19, 2026.

## Threat Group & Attack Vector

The retained source describes the attack path as follows: Lapsus$; single compromised employee account. The canonical record does not add intrusion steps beyond those supported by the source. [1](#source-1)

### Actors

- **Lapsus$** — identified in the supported attack description. [1](#source-1)

### TTPs

- No specific MITRE ATT\&CK technique is currently mapped for this case.

## Response

The reviewed source does not describe containment, notification, or restoration steps in enough detail to summarize them responsibly.

This account is bounded to [DEV-0537 criminal actor targeting organizations](https://www.microsoft.com/security/blog/2022/03/22/dev-0537-criminal-actor-targeting-organizations-for-data-exfiltration-and-destruction/). Details absent from that evidence are left unresolved rather than inferred. [1](#source-1)

## Assets

[Download the case-scoped STIX 2.1 bundle](<https://www.ally.security/incidents/microsoft-security-incident-2022/stix.json>)

## Sources

Primary source records used to research this incident.

<a id="source-1"></a>

### DEV-0537 criminal actor targeting organizations

research · Microsoft

<https://www.microsoft.com/security/blog/2022/03/22/dev-0537-criminal-actor-targeting-organizations-for-data-exfiltration-and-destruction/>

<details>
<summary>Evidence ledger</summary>

Review the supporting structured claims.

1. **Resulted In · 89% confidence · current**  
   Microsoft security incident: Lapsus$; single compromised employee account.
2. **Resulted In · 100% confidence · current**  
   Microsoft security incident: The reviewed source documents the microsoft security incident involving Microsoft.
3. **Affected Organization · 100% confidence · current**  
   Microsoft security incident: Microsoft
4. **Occurred At · 100% confidence · current**  
   Documented public update: 2022-03-22
5. **Resulted In · 84% confidence · current**  
   Microsoft security incident: Partial source code for Bing/Cortana and other products accessed.

</details>