OpenCanary: HTTP Form POST Login Attempt Observed on Port Service
Alerts on OpenCanary HTTP Form POST events indicating a login attempt to an exposed service.
- Product
- opencanary
- Category
- application
- Author
- Security Onion Solutions (SigmaHQ), DRL 1.1
- Published
- 2024-03-08
- Updated
- 2026-07-31
ATT&CK techniques
Initial AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags OpenCanary events where an HTTP service on an OpenCanary node records a login attempt sent via an HTTP POST using a form-based request. Login attempts over POST are a common initial step in credential guessing and automated probing against exposed web services. It relies on OpenCanary application logs indicating a form POST login attempt (logtype 3001).
Reporting behind it
- opencanary.readthedocs.iohttps://opencanary.readthedocs.io/en/latest/starting/configuration.html#services-configuration
- github.comhttps://github.com/thinkst/opencanary/blob/a0896adfcaf0328cfd5829fe10d2878c7445138e/opencanary/logger.py#L52
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/application/opencanary/opencanary_http_post_login_attempt.yml
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "OpenCanary: HTTP Form POST Login Attempt Observed on Port Service"
id: 886245f3-5576-4828-9de0-b0fb67942c3b
status: test
description: This rule flags OpenCanary events where an HTTP service on an OpenCanary node records a login attempt sent via an HTTP POST using a form-based request. Login attempts over POST are a common initial step in credential guessing and automated probing against exposed web services. It relies on OpenCanary application logs indicating a form POST login attempt (logtype 3001).
references:
- https://opencanary.readthedocs.io/en/latest/starting/configuration.html#services-configuration
- https://github.com/thinkst/opencanary/blob/a0896adfcaf0328cfd5829fe10d2878c7445138e/opencanary/logger.py#L52
- https://github.com/SigmaHQ/sigma/blob/master/rules/application/opencanary/opencanary_http_post_login_attempt.yml
author: Security Onion Solutions, Huntrule Team
date: 2024-03-08
tags:
- attack.initial-access
- attack.t1190
logsource:
category: application
product: opencanary
detection:
selection:
logtype: 3001
condition: selection
falsepositives:
- Unlikely
level: high
license: DRL-1.1
related:
- id: af1ac430-df6b-4b38-b976-0b52f07a0252
type: derived