Detection rules › Splunk
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 coverage
| Tactic | Techniques |
|---|---|
| Initial Access | T1190 Exploit Public-Facing Application |
Rule body splunk
name: MOVEit Empty Key Fingerprint Authentication Attempt
id: 1a537acc-199f-4713-b5d7-3d98c05ab932
version: 7
creation_date: '2024-07-24'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: Hunting
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.
data_source: []
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/
analytic_story:
- MOVEit Transfer Authentication Bypass
- Hellcat Ransomware
asset_type: Web Server
cve:
- CVE-2024-5806
mitre_attack_id:
- T1190
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
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
test_type: unit
Stages and Predicates
Stage 1: search
`moveit_sftp_logs` "UserAuthRequestHandler: SftpPublicKeyAuthenticator: Attempted to authenticate empty public key fingerprint"
Stage 2: stats
| stats count
BY source _raw
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `moveit_empty_key_fingerprint_authentication_attempt_filter`
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
sourcetype | eq |
|
Search terms
Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.
| Stage | Term |
|---|---|
| 1 | "UserAuthRequestHandler: SftpPublicKeyAuthenticator: Attempted to authenticate empty public key fingerprint" |