---
title: "Rackspace security incident"
description: "What the retained public evidence establishes about the Rackspace 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/rackspace-security-incident-2022"
markdown_url: "https://www.ally.security/incidents/rackspace-security-incident-2022.md"
stix_url: "https://www.ally.security/incidents/rackspace-security-incident-2022/stix.json"
---

# Rackspace security incident

Play ransomware; ProxyNotShell Exchange zero-day. Hosted Exchange email outage for thousands of customers.

Last modified Sep 19, 2026 · 1 source

## Summary

- **Environment:** Cloud hosting
- **Operational impact:** Hosted Exchange email outage for thousands of customers
- **Financial impact:** No financial figure is established by the reviewed source evidence

## What happened

In 2022, Rackspace experienced an incident in its cloud hosting environment. The retained source describes the attack path as follows: Play ransomware; ProxyNotShell Exchange zero-day. [1](#source-1)

The documented consequence was: Hosted Exchange email outage for thousands of customers. [1](#source-1)

## Impact

- Documented impact: Hosted Exchange email outage for thousands of customers. [1](#source-1)
- No financial loss, ransom amount, recovery cost, or regulatory penalty is established by the reviewed source evidence.

## Threat Group & Attack Vector

The retained source describes the attack path as follows: Play ransomware; ProxyNotShell Exchange zero-day. The canonical record does not add intrusion steps beyond those supported by the source. [1](#source-1)

### Actors

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

### TTPs

- [T1486 — Data Encrypted for Impact](https://attack.mitre.org/techniques/T1486/) — mapped from the cited behavior. [1](#source-1)
- [T1190 — Exploit Public-Facing Application](https://attack.mitre.org/techniques/T1190/) — mapped from the cited behavior. [1](#source-1)

## Response

The retained source describes containment action intended to limit further access or disruption. [1](#source-1)
The retained source describes a forensic or specialist investigation of the incident. [1](#source-1)

This account is bounded to [Rackspace Technology Form 10-K](https://www.sec.gov/Archives/edgar/data/1810019/000181001923000034/rxt-20221231.htm). 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/rackspace-security-incident-2022/stix.json>)

## Sources

Primary source records used to research this incident.

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

### Rackspace Technology Form 10-K

regulatory · U.S. Securities and Exchange Commission

<https://www.sec.gov/Archives/edgar/data/1810019/000181001923000034/rxt-20221231.htm>

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

Review the supporting structured claims.

1. **Used Attack Technique · 90% confidence · current**  
   Rackspace security incident: https://attack.mitre.org/techniques/T1486/
2. **Resulted In · 88% confidence · current**  
   Rackspace security incident: Hosted Exchange email outage for thousands of customers.
3. **Resulted In · 90% confidence · current**  
   Rackspace security incident: The retained source describes a forensic or specialist investigation of the incident.
4. **Affected Organization · 100% confidence · current**  
   Rackspace security incident: Rackspace
5. **Used Attack Technique · 90% confidence · current**  
   Rackspace security incident: https://attack.mitre.org/techniques/T1190/
6. **Resulted In · 100% confidence · current**  
   Rackspace security incident: The reviewed source documents the rackspace security incident involving Rackspace.
7. **Resulted In · 86% confidence · current**  
   Rackspace security incident: Play ransomware; ProxyNotShell Exchange zero-day.
8. **Resulted In · 90% confidence · current**  
   Rackspace security incident: The retained source describes containment action intended to limit further access or disruption.

</details>