IP Threat Report
138.91.23.81
ABUSE.MOM — BEHAVE OR GET EXPOSED
Geolocation & Classification
Detection Signatures
| Signature | Description | Points | Severity |
|---|---|---|---|
| Danger strong hits: 13 | High-risk paths: shells, RCE vectors, exploits | +100 | |
| Danger medium hits: 40 | Medium-risk: admin panels, config files | +60 | |
| Burst: 12 req / 2s | Abnormally fast request rate — automated scanning | +35 | |
| Burst: 43 req / 10s | Abnormally fast request rate — automated scanning | +35 | |
| Burst: 41 req / 10s | Abnormally fast request rate — automated scanning | +35 | |
| Danger strong hits: 17 | High-risk paths: shells, RCE vectors, exploits | +100 | |
| Danger medium hits: 90 | Medium-risk: admin panels, config files | +60 | |
| 404 ratio >= 60% | Majority of requests returned 404 — enumeration | +25 | |
| Burst: 42 req / 10s | Abnormally fast request rate — automated scanning | +35 | |
| Burst: 40 req / 10s | Abnormally fast request rate — automated scanning | +35 |
Observed Activity
Reconstructed HTTP requests from server access logs. Target domains redacted for security.
* Typical request patterns for detected signatures. Actual target domains are redacted.
Timeline
Network Provider
Recommendations
Actions taken & recommended
- IP 138.91.23.81 is blocked at application level (HTTP 403)
- Consider blocking at firewall level (iptables/CSF) to reduce server load
- Report abuse to the network provider via their abuse contact
- Ensure sensitive files (.env, .git, backups) are not accessible from the web
🌊 Traffic Flood Defense
IP 138.91.23.81 is generating excessive traffic. Limit connections per source IP. Enable geographic blocking if traffic from this region is unexpected.
🔎 Path Enumeration Protection
Block scanning from 138.91.23.81: rate-limit 404 responses per IP, deploy a honeypot 404 page, ensure no backup files are web-accessible.
Open Ports & Services
Network reconnaissance data from Shodan. Open ports may indicate running services, misconfigurations, or potential attack surfaces.
| Port | Service | Risk | Description |
|---|---|---|---|
| 443 | HTTPS | Low | HTTPS web server — encrypted web traffic |
Data source: Shodan InternetDB. Scanned independently of abuse.mom.
Blacklist Status (DNSBL)
This IP was checked against major DNS-based blacklists used by mail servers and firewalls worldwide.
Checked: Spamhaus, SpamCop, Barracuda, SORBS, CBL, UCEProtect. Results may change over time.
Threat Analysis
138.91.23.81 has been assigned a threat score of 255/100 (Critical). With this rating, the IP falls into the critical severity bracket — among the most dangerous addresses in our monitoring database.
The following attack categories were identified:
📊 Threat Analysis
Our monitoring infrastructure has identified 138.91.23.81, geolocated to Osaka, Japan, operating on the network of Microsoft Corporation, as a source of suspicious network activity. The address has been active for 1 days in our monitoring system, producing 13 flagged requests at a rate of ~13/day. Classified as a hosting IP, this address likely runs on a rented server or cloud instance. Attackers prefer datacenter IPs for their high bandwidth and disposable nature. The dual attack vectors of Request Flooding combined with Path Enumeration indicate a coordinated assault rather than opportunistic scanning. Our records show 101 malicious IPs originating from Japan, positioning it as a significant contributor to global threat activity. With a threat score of 255/100, this IP is among the most dangerous addresses in our database. Immediate and complete blocking is strongly recommended.
This IP belongs to a hosting or data center provider. Malicious traffic from hosting infrastructure often originates from compromised VPS instances, rented servers used for scanning campaigns, or abused free-tier cloud accounts. Hosting providers typically respond to abuse reports within 24-72 hours.
Related Threats
Security Intelligence
💡 SQL Injection Campaigns
SQL injection remains one of the most common web attack vectors. Attackers inject malicious SQL code through input fields to extract database contents, modify data, or gain administrative access. Automated scanners test for SQLi vulnerabilities at massive scale.
💡 DNS-Based Threat Detection
Monitoring DNS queries reveals malicious activity including command-and-control communication, data exfiltration through DNS tunneling, and connections to known malicious domains. DNS is often the first indicator of compromise in network forensics.