Kuiper ransomware group
Kuiper is one of the extortion operations we watch continuously. This page covers what is known about the group and the current state of its leak site.
Who they are
Kuiper is a relatively new ransomware strain first analyzed in April 2023, notable for being written in Rust and designed to target multiple platforms, including Windows, Linux, and ESXi environments. The ransomware encrypts files with ChaCha20 symmetric encryption, securing keys with Curve25519, and appends the .kuiper extension to affected files. Kuiper operates under a double-extortion model, exfiltrating data before encryption and threatening to leak it on a Tor-hosted site if the ransom is not paid. Initial infection vectors are not widely documented, but analysis suggests potential use of compromised credentials, phishing, or exploitation of exposed services. The ransomware contains evasion techniques such as process termination, shadow copy deletion, and targeting of backup files to hinder recovery. Public reporting on Kuiper remains limited, indicating it may be in an early operational stage or used by a small number of actors.
Current status
Kuiper's leak site is not answering. Sites go dark for infrastructure trouble, a deliberate quiet period, or a takedown, and a good number return weeks later under the same name, so the entry stays on the list either way.
Which organisations this group has named, and when, is part of the SINON platform rather than this page. Create an account to search it, or to be told automatically if a name you care about turns up.
Sectors targeted
This group does not state an industry on its site, so we have nothing reliable to report. Most crews are opportunistic rather than sector-specific in any case — they hit what they can reach.
Watching for your name
If Kuiper posts your company, a supplier or a subsidiary, you want to hear it from us rather than from a journalist. SINON checks these sites continuously and alerts on the names you give it.
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