Chainalysis Reactivates Core Monitoring Tools After Massive User Data Breach
Blockchain analytics firm Chainalysis has restored its primary monitoring platforms—Reactor, KYT, and Address Screening—after a security incident revealed login information for every user.
The company announced the return of Reactor and its screening products at 18:50 UTC on November 7, and began emailing customers step‑by‑step instructions for reconnecting with enhanced security measures.
The preceding snapshot reflects the status as of November 7 before the restoration announcement and is not a current representation of service availability.
What access requires
KYT and Address Screening access is phased. Once access is granted, all users must reset passwords and rotate API keys as applicable before registering transactions.
Before registering transactions KYT and Address Screening 1234 Submit trusted IPs For the allowlist Access granted Restoration is phased Reset passwords Rotate API keys as applicable Then register transactions
Reactor, Investigations API and Rapid Lookup remain under maintenance in the captured Nov. 7 status.
Under the current recovery plan, users who have regained access must reset passwords, rotate API keys where applicable, and then proceed to register transactions.
The recovery follows a breach disclosed on October 31 that exposed names, usernames, password hashes and live login tokens for all users. The October 30 notice listed accessed user IDs, email addresses and organization role labels.
On November 4 Chainalysis detected exposure of real‑time login tokens and other credential artifacts on its platform. While no evidence was found that investigation data or attribution was manipulated, the company indicated abnormal activity on that day led to the temporary decommissioning of KYT, other address‑screening tools and the login page. Customers whose accounts appeared compromised were notified.
Chainalysis instructed affected users to submit trusted IP addresses to the allow‑list through their account team or support. After access is restored, customers must change passwords and rotate any applicable API keys before they can register transactions.