Potential Okta Password Spray (Multi-Source)
Description
Detects potential password spray attacks where multiple source IPs target multiple Okta user accounts within a time window, indicating coordinated attacks using IP rotation to evade single-source detection.
Query · esql
FROM logs-okta.system-* METADATA _id, _version, _index
| WHERE
data_stream.dataset == "okta.system"
AND (event.action LIKE "user.authentication.*" OR event.action == "user.session.start")
AND okta.outcome.reason IN ("INVALID_CREDENTIALS", "LOCKED_OUT")
AND okta.actor.alternate_id IS NOT NULL
// Bucket into 15-minute windows and create user-source mapping for context
| EVAL
Esql.time_bucket = DATE_TRUNC(15 minutes, @timestamp),
Esql.user_source_info = CONCAT(
"{\"user\":\"", okta.actor.alternate_id,
"\",\"ip\":\"", COALESCE(okta.client.ip::STRING, "unknown"),
"\",\"user_agent\":\"", COALESCE(okta.client.user_agent.raw_user_agent, "unknown"), "\"}"
)
// Aggregate across entire tenant per time bucket to detect distributed spray
| STATS
Esql.unique_users = COUNT_DISTINCT(okta.actor.alternate_id),
Esql.unique_source_ips = COUNT_DISTINCT(okta.client.ip),
Esql.total_attempts = COUNT(*),
Esql.unique_user_agents = COUNT_DISTINCT(okta.client.user_agent.raw_user_agent),
Esql.unique_asns = COUNT_DISTINCT(source.as.number),
Esql.unique_countries = COUNT_DISTINCT(client.geo.country_name),
Esql.first_seen = MIN(@timestamp),
Esql.last_seen = MAX(@timestamp),
Esql.target_users = VALUES(okta.actor.alternate_id),
Esql.source_ip_values = VALUES(okta.client.ip),
Esql.user_source_mapping = VALUES(Esql.user_source_info),
Esql.event_action_values = VALUES(event.action),
Esql.user_agent_values = VALUES(okta.client.user_agent.raw_user_agent),
Esql.device_values = VALUES(okta.client.device),
Esql.is_proxy_values = VALUES(okta.security_context.is_proxy),
Esql.geo_country_values = VALUES(client.geo.country_name),
Esql.geo_city_values = VALUES(client.geo.city_name),
Esql.source_asn_values = VALUES(source.as.number),
Esql.source_asn_org_values = VALUES(source.as.organization.name),
Esql.threat_suspected_values = VALUES(okta.debug_context.debug_data.threat_suspected),
Esql.risk_level_values = VALUES(okta.debug_context.debug_data.risk_level),
Esql.risk_reasons_values = VALUES(okta.debug_context.debug_data.risk_reasons)
BY Esql.time_bucket
// Calculate spray metrics
| EVAL
Esql.attempts_per_user = Esql.total_attempts * 1.0 / Esql.unique_users,
Esql.attempts_per_ip = Esql.total_attempts * 1.0 / Esql.unique_source_ips,
Esql.users_per_ip = Esql.unique_users * 1.0 / Esql.unique_source_ips
// Distributed spray: many IPs, many users, moderate spread across both
// Key differentiator: attacks come from multiple IPs (evading per-IP rules)
| WHERE
Esql.unique_source_ips >= 5
AND Esql.unique_users >= 8
AND Esql.total_attempts >= 25
AND Esql.attempts_per_user <= 5.0
AND Esql.users_per_ip >= 1.0
| SORT Esql.total_attempts DESC
| KEEP Esql.*
Implementation guide
The Okta Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.
Known false positives
- Large enterprises with many users experiencing simultaneous password issues during credential rotation events.
- Automated monitoring or penetration testing tools scanning from multiple IPs.
Analyst notes
Investigating Potential Okta Password Spray (Multi-Source)
This rule identifies coordinated password spray attacks where multiple source IPs target multiple user accounts within a time window. This pattern indicates attackers using IP rotation to evade single-source detection while spraying passwords across the organization.
Possible investigation steps
- Review the list of targeted user accounts and check if any authentications succeeded.
- Examine the source IPs and their ASN ownership for signs of proxy, VPN, or cloud infrastructure.
- Check if Okta flagged any of the sources as known threats or proxies.
- Analyze the attempts-per-user ratio to confirm spray behavior versus brute force.
- Review the geographic distribution of source IPs for coordination patterns.
- Cross-reference with successful authentication events to identify potential compromises.
False positive analysis
- Organization-wide password rotation or expiration events may cause widespread authentication failures.
- Misconfigured SSO or SAML integrations can cause batch failures from legitimate infrastructure.
- Penetration testing should be coordinated and whitelisted in advance.
Response and remediation
- If attack is confirmed, notify affected users and enforce password resets for potentially compromised accounts.
- Block attacking IP ranges at the network perimeter.
- Enable or strengthen MFA for targeted accounts.
- Review Okta sign-on policies to add additional friction for suspicious authentication patterns.
- Consider temporary lockdowns for highly targeted accounts.