CAPEC-307
TCP RPC Scan
An adversary scans for RPC services listing on a Unix/Linux host.
On this page
This type of scan can be obtained via native operating system utilities or via port scanners like nmap. When performed by a scanner, an RPC datagram is sent to a list of UDP ports and the response is recorded. Particular types of responses can be indicative of well-known RPC services running on a UDP port. Discovering RPC services gives the adversary potential targets to attack, as some RPC services are insecure by default.
Direct RPC scans that bypass portmapper/sunrpc are typically slow compare to other scan types, are easily detected by IPS/IDS systems, and can only detect open ports when an RPC service responds. ICMP diagnostic message responses can help identify closed ports, however filtered and unfiltered ports cannot be identified through TCP RPC scans. There are two general approaches to RPC scanning: One is to use a native operating system utility, or script, to query the portmapper/rpcbind application running on port 111. Portmapper will return a list of registered RPC services. Alternately, one can use a port scanner or script to scan for RPC services directly.
Ask an AI about this attack pattern
Show the prompt
Explain the attack pattern CAPEC-307: TCP RPC Scan: how it unfolds, what it needs and how to prevent and detect it in my systems. Use https://capec.mitre.org/data/definitions/307.html and https://cve.bz/cve/capec/307?via=ask-ai-copy, which lists recent CVEs with the weaknesses it exploits. Cite the sources.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this attack pattern's id and public links.
How the attack unfolds
Experiment
They probe what they found.
An adversary sends RCP packets to target ports.
An adversary uses the response from the target to determine which, if any, RPC service is running on that port. Responses will vary based on which RPC service is running.
Prerequisites
RPC scanning requires no special privileges when it is performed via a native system utility.
Resources required
The ability to craft custom RPC datagrams for use during network reconnaissance via native OS utilities or a port scanning tool. By tailoring the bytes injected one can scan for specific RPC-registered services. Depending upon the method used it may be necessary to sniff the network in order to see the response.
Consequences
| Impact | Affects | Note |
|---|---|---|
| Other | Confidentiality | |
| Bypass Protection Mechanism, Hide Activities | Confidentiality, Access Control, Authorization |
Mitigations
Typically, an IDS/IPS system is very effective against this type of attack.
Weaknesses it exploits
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
Recent CVEs with these weaknesses
- 4.3CVE-2026-124944
Information disclosure in the Marionette component. This vulnerability was fixed in Firefox 160.
- 4.3CVE-2026-124941
Information disclosure in the Security: RLBox component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.
- 4.3CVE-2026-124930
Information disclosure in the Address Bar component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.
- 4.3CVE-2026-124929
Information disclosure in the Layout: Form Controls component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.
- 4.3CVE-2026-124925
Information disclosure in the Layout component. This vulnerability was fixed in Firefox 160.
- 4.3CVE-2026-124909
Information disclosure in the Private Browsing component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.
- 5.3CVE-2026-96769
The Extend B2B - Companies and Users Management for WooCommerce plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 2.1.4 via the register_company_api. This makes it possible for unaut…
- 7.5CVE-2026-63644
bird-lg-go is a BIRD looking glass in Go. Prior to version 1.4.7, unsanitized input path enables arbitrary local file read, allowing an unauthenticated remote attacker to read sensitive files such as /etc/shadow and /root/.bash_history. Th…
The newest records naming one of them. Each weakness's page lists them all.
Related attack patterns
- Part of
- CAPEC-300 Port Scanning
MITRE's words, unchanged: CAPEC-307 at MITRE. CAPEC is Copyright © 2007–2026, The MITRE Corporation, used under the CAPEC terms of use: “The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use Common Attack Pattern Enumeration and Classification (CAPEC™) for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE’s copyright designation and this license in any such copy.” CAPEC and the CAPEC logo are trademarks of The MITRE Corporation. Credits. All attack patterns.