DNS Query to External Service Interaction Domains
Detects DNS queries to well-known out-of-band application security testing (OAST) and callback domains. These services (e.g. Burp Collaborator, interactsh, canarytokens, dnslog.cn) are used by security researchers…
Description
Detects DNS queries to well-known out-of-band application security testing (OAST) and callback domains. These services (e.g. Burp Collaborator, interactsh, canarytokens, dnslog.cn) are used by security researchers and attackers alike to confirm blind vulnerabilities such as SSRF, XXE, blind RCE, and Log4Shell-style injections, where the exploit payload triggers an external DNS lookup to a controlled domain. A detection indicates that a host on your network resolved one of these domains, which may mean: (1) an attacker is actively probing or exploiting a vulnerable service and using the callback to confirm code execution or data exfiltration, (2) a security scanner (e.g. Nuclei, Gobies) is running against internal targets. Investigate the source host, the full DNS query string (the unique subdomain prefix encodes the callback session), and any concurrent outbound connections or process activity to determine intent.
Detection logic
Detection requirements
- Platform
- ContainersESXiIaaSLinuxmacOSNetwork DevicesPREWindows
The rule states no platform. This is derived from the 2 ATT&CK techniques it maps to.
- Log source category
- dns
Known benign triggers
- Legitimate security scanning.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| github.com/SigmaHQ/sigma/pull/5724#issuecomment-3466382234 | Only this detection cites it |
| hunt.io/blog/open-directory-nginx-rift-ghost-cms-multi-cve | Only this detection cites it |
| twitter.com/breakersall/status/1533493587828260866 | Only this detection cites it |
| www.bitdefender.com/en-us/blog/businessinsights/bitdefender-advisory-critical-unauthenticated-rce-windows-server-update-services-cve-2025-59287 | Only this detection cites it |
From the source
- At source
- Open at source
- Upstream identifier
- aff715fa-4dd5-497a-8db3-910bea555566
- Tagged by the source as
- attack.initial-accessattack.reconnaissance
Licence
- Published under
- Detection Rule License 1.1Read the licence
- Attribution
- Required
Authorship
- Published
- Oct 14, 2026
- Version
- 3