splunk_escuHunting

MOVEit Empty Key Fingerprint Authentication Attempt

This detection identifies attempts to authenticate with an empty public key fingerprint in Progress MOVEit Transfer, which is a key indicator of potential exploitation of the CVE-2024-5806 vulnerability. Such attempts are characteristic of the authentication bypass technique used in this vulnerability, where attackers try to impersonate valid users without providing proper credentials. While occasional empty key fingerprint authentication attempts might occur due to misconfigurations, a sudden increase or attempts from unexpected sources could signify malicious activity. This analytic helps security teams identify and investigate potential exploitation attempts of the MOVEit Transfer authentication bypass vulnerability.

MITRE ATT&CK

T1190

initial-access

Detection Query

`moveit_sftp_logs` "UserAuthRequestHandler: SftpPublicKeyAuthenticator: Attempted to authenticate empty public key fingerprint"
  | stats count
    BY source _raw
  | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)`
  | `moveit_empty_key_fingerprint_authentication_attempt_filter`

Author

Michael Haag, Splunk

Created

2026-02-25

References

https://labs.watchtowr.com/auth-bypass-in-un-limited-scenarios-progress-moveit-transfer-cve-2024-5806/

Tags

MOVEit Transfer Authentication BypassHellcat Ransomware

Raw Content

name: MOVEit Empty Key Fingerprint Authentication Attempt
id: 1a537acc-199f-4713-b5d7-3d98c05ab932
version: 6
date: '2026-02-25'
author: Michael Haag, Splunk
data_source: []
type: Hunting
status: production
description: This detection identifies attempts to authenticate with an empty public key fingerprint in Progress MOVEit Transfer, which is a key indicator of potential exploitation of the CVE-2024-5806 vulnerability. Such attempts are characteristic of the authentication bypass technique used in this vulnerability, where attackers try to impersonate valid users without providing proper credentials. While occasional empty key fingerprint authentication attempts might occur due to misconfigurations, a sudden increase or attempts from unexpected sources could signify malicious activity. This analytic helps security teams identify and investigate potential exploitation attempts of the MOVEit Transfer authentication bypass vulnerability.
search: |-
    `moveit_sftp_logs` "UserAuthRequestHandler: SftpPublicKeyAuthenticator: Attempted to authenticate empty public key fingerprint"
      | stats count
        BY source _raw
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `moveit_empty_key_fingerprint_authentication_attempt_filter`
how_to_implement: The MOVEit logs must be collected in Splunk. Currently, there is no TA available for MOVEit. Modify the analytic as needed to match the log format of your environment.
known_false_positives: False positives may occur, therefore utilize the analytic as a jump off point to identify potential empty key fingerprint authentication attempts.
references:
    - https://labs.watchtowr.com/auth-bypass-in-un-limited-scenarios-progress-moveit-transfer-cve-2024-5806/
tags:
    analytic_story:
        - MOVEit Transfer Authentication Bypass
        - Hellcat Ransomware
    asset_type: Web Server
    mitre_attack_id:
        - T1190
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: endpoint
    cve:
        - CVE-2024-5806
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1190/moveit/SftpServer.log
          sourcetype: sftp_server_logs
          source: sftp_server_logs