ABUSE.MOM
THREAT REPORT

IP Threat Report
165.154.51.221

ABUSE.MOM — BEHAVE OR GET EXPOSED

Generated: 2026-05-30 07:18:57
First seen: 2026-03-10 08:00:05
Last seen: 2026-05-15 19:00:06
125

⛔ Verdict: BLOCK

This IP address has been classified as a source of malicious automated activity. Threat score: 125/100. Total malicious requests observed: 3.

BOT_UAUA_CHANGEDRATIO_404BURSTREFERER
01

Geolocation & Classification

IP Address
165.154.51.221
Type
Hosting
Country
🇹🇭 Thailand
City
Bangkok
ISP
UCLOUD INFORMATION TECHNOLOGY (HK) LIMITED
Organization
Ucloud Information Technology (hk) Limited
Autonomous System
AS135377 UCLOUD INFORMATION TECHNOLOGY (HK) LIMITED
Hit Count
3
02

Detection Signatures

SignatureDescriptionPointsSeverity
UA bot: Go-http-clientKnown bot/crawler User-Agent detected+40
UA changed for same IPMultiple User-Agents — bot rotation technique+25
404 ratio >= 60%Majority of requests returned 404 — enumeration+25
404 ratio 40-60%Majority of requests returned 404 — enumeration+15
Burst: 6 req / 2sAbnormally fast request rate — automated scanning+35
Foreign referer seenReferer from unrelated external domain+10
Σ = 150
03

Observed Activity

Reconstructed HTTP requests from server access logs. Target domains redacted for security.

[redacted]
GET
/
200
[redacted]
GET
/page
200
Requests shown: 2 · HTTP 404: 0 · Dangerous patterns: 0

* Typical request patterns for detected signatures. Actual target domains are redacted.

04

Timeline

2026-03-10 08:00:05
First malicious request detected
IP entered monitoring from server access logs
During observation
Multiple detection signatures triggered
UA bot: Go-http-client (+40), UA changed for same IP (+25), 404 ratio >= 60% (+25)
2026-05-15 19:00:06
Last malicious request observed
Total score reached: 125/100
Next cycle
IP blocked — all subsequent requests denied (HTTP 403)
Added to blocklist automatically
05

Network Provider

UCLOUD INFORMATION TECHNOLOGY (HK) LIMITED
AS135377 · 🇹🇭 Thailand
06

Recommendations

Actions taken & recommended

  • IP 165.154.51.221 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

🤖 User-Agent Anomaly Defense

IP 165.154.51.221 shows suspicious UA behavior. Block empty User-Agent requests. Implement JavaScript-based bot detection for sensitive endpoints.

🔎 Path Enumeration Protection

Block scanning from 165.154.51.221: rate-limit 404 responses per IP, deploy a honeypot 404 page, ensure no backup files are web-accessible.

🌊 Flood / DDoS Mitigation

Implement limit_req_zone in nginx. Deploy CDN with DDoS protection. Configure SYN cookies and connection tracking to throttle 165.154.51.221.

09

Blacklist Status (DNSBL)

This IP was checked against major DNS-based blacklists used by mail servers and firewalls worldwide.

⛔ LISTED
Spamhaus ZEN

Checked: Spamhaus, SpamCop, Barracuda, SORBS, CBL, UCEProtect. Results may change over time.

10

Threat Analysis

165.154.51.221 has been assigned a threat score of 125/100 (Critical). A score this high marks a critical threat actor. This address has demonstrated persistent, aggressive malicious behavior across multiple detection vectors.

The following attack categories were identified:

User-Agent AnomalyPath EnumerationRequest Flooding

📊 Threat Analysis

Threat intelligence analysis has linked 165.154.51.221 to malicious activity originating from Bangkok, Thailand, operating on the network of UCLOUD INFORMATION TECHNOLOGY (HK) LIMITED. The address has been under observation since its initial detection. The address has been active for 66 days in our monitoring system, producing 3 flagged requests at a rate of ~0/day. Operating from datacenter infrastructure, this IP is typical of addresses used in organized attack operations. Cloud and VPS providers are commonly exploited as launching platforms for automated scanning. The combination of 3 distinct attack vectors indicates a sophisticated, multi-pronged threat actor deploying automated tools that probe multiple attack surfaces simultaneously. With 102 flagged addresses, Thailand represents a significant presence in our threat database. With a threat score of 125/100, 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.

11

Related Threats

🇹🇭 Top threats from Thailand

8.213.218.53 (305)118.175.94.213 (268)98.159.43.111 (255)98.159.43.149 (255)98.159.43.117 (255)View all →

🏢 Same network: AS135377

118.194.251.58 (125)165.154.120.253 (125)118.194.250.95 (125)118.194.251.101 (125)165.154.120.223 (125)View all →
12

Security Intelligence

💡 User-Agent Analysis Techniques

Analyzing User-Agent strings reveals automated tools masquerading as legitimate browsers. Inconsistencies between claimed browser capabilities and actual behavior, impossible version combinations, and known scanner signatures help identify malicious clients.

💡 IP Geolocation Accuracy Limitations

IP geolocation databases provide approximate locations with varying accuracy. City-level geolocation is typically 50-80% accurate, while country-level exceeds 95%. VPNs, proxies, and mobile networks further reduce reliability, making geolocation a useful but imperfect intelligence signal.

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