Samirbous
896b6a214a
* Update credential_access_rare_webdav_destination.toml * Update credential_access_rare_webdav_destination.toml
98 lines
3.9 KiB
TOML
98 lines
3.9 KiB
TOML
[metadata]
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creation_date = "2025/04/28"
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integration = ["endpoint", "system", "windows", "m365_defender", "crowdstrike"]
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maturity = "production"
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updated_date = "2025/12/05"
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[rule]
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author = ["Elastic"]
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description = """
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Identifies rare connection attempts to a Web Distributed Authoring and Versioning (WebDAV) resource. Attackers may
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inject WebDAV paths in files or features opened by a victim user to leak their NTLM credentials via forced
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authentication.
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"""
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from = "now-3660s"
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language = "esql"
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license = "Elastic License v2"
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name = "Rare Connection to WebDAV Target"
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note = """## Triage and analysis
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### Investigating Rare Connection to WebDAV Target
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### Possible investigation steps
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- Examine the reputation of the destination domain or IP address.
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- Verify if the target user opened any attachments or clicked links pointing to the same target within seconds from the alert timestamp.
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- Correlate the findings with other security logs and alerts to identify any patterns or additional indicators of compromise related to the potential relay attack.
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### False positive analysis
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- User accessing legit WebDAV resources.
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### Response and remediation
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- Conduct a password reset for the target account that may have been compromised or are at risk, ensuring the use of strong, unique passwords.
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- Verify whether other users were targeted but did not open the lure..
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- Escalate the incident to the security operations center (SOC) or incident response team for further investigation and to determine the full scope of the breach.
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- Conduct a post-incident review to identify any gaps in security controls and update policies or procedures to prevent recurrence, ensuring lessons learned are applied to improve overall security posture."""
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references = ["https://attack.mitre.org/techniques/T1187/"]
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risk_score = 47
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rule_id = "6756ee27-9152-479b-9b73-54b5bbda301c"
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severity = "medium"
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tags = [
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"Domain: Endpoint",
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"OS: Windows",
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"Use Case: Threat Detection",
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"Tactic: Credential Access",
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"Data Source: Elastic Defend",
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"Data Source: Windows Security Event Logs",
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"Data Source: Microsoft Defender for Endpoint",
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"Data Source: Crowdstrike",
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"Resources: Investigation Guide",
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]
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timestamp_override = "event.ingested"
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type = "esql"
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query = '''
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from logs-endpoint.events.process-*, logs-windows.sysmon_operational-*, logs-system.security-*, logs-windows.*, winlogbeat-*, logs-crowdstrike.fdr*, logs-m365_defender.event-* METADATA _id, _version, _index
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| where
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@timestamp > now() - 8 hours and
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event.category == "process" and
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event.type == "start" and
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process.name == "rundll32.exe" and
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process.command_line like "*DavSetCookie*"
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| keep host.id, process.command_line, user.name
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| grok process.command_line """(?<Esql.server_webdav_cookie>DavSetCookie .* http)"""
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| eval
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Esql.server_webdav_cookie_replace = replace(Esql.server_webdav_cookie, "(DavSetCookie | http)", "")
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| where
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Esql.server_webdav_cookie_replace is not null and
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Esql.server_webdav_cookie_replace rlike """(([a-zA-Z0-9-]+\.)+[a-zA-Z]{2,3}(@SSL.*)*|(\d{1,3}\.){3}\d{1,3})""" and
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not Esql.server_webdav_cookie_replace in ("www.google.com@SSL", "www.elastic.co@SSL") and
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not Esql.server_webdav_cookie_replace rlike """(10\.(\d{1,3}\.){2}\d{1,3}|172\.(1[6-9]|2\d|3[0-1])\.(\d{1,3}\.)\d{1,3}|192\.168\.(\d{1,3}\.)\d{1,3})"""
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| stats
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Esql.event_count = count(*),
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Esql.host_id_count_distinct = count_distinct(host.id),
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Esql.host_id_values = values(host.id),
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Esql.user_name_values = values(user.name)
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by Esql.server_webdav_cookie_replace
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| where
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Esql.host_id_count_distinct == 1 and
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Esql.event_count <= 3
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'''
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[[rule.threat]]
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framework = "MITRE ATT&CK"
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[[rule.threat.technique]]
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id = "T1187"
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name = "Forced Authentication"
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reference = "https://attack.mitre.org/techniques/T1187/"
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[rule.threat.tactic]
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id = "TA0006"
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name = "Credential Access"
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reference = "https://attack.mitre.org/tactics/TA0006/"
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