ABUSE.MOM
THREAT REPORT

IP Threat Report
205.169.39.138

ABUSE.MOM — BEHAVE OR GET EXPOSED

Generated: 2026-05-29 07:27:19
First seen: 2026-05-11 08:00:07
Last seen: 2026-05-11 08:00:07
70

⛔ Verdict: BLOCK

This IP address has been classified as a source of malicious automated activity. Threat score: 70/100. Total malicious requests observed: 1.

UA_CHANGEDBURSTREFERER
01

Geolocation & Classification

IP Address
205.169.39.138
Type
Residential
Country
🇺🇸 United States
City
Santa Clara
ISP
CenturyLink Communications
Organization
Palo Alto Networks, Inc
Autonomous System
AS3356 Level 3 Parent, LLC
Hit Count
1
02

Detection Signatures

SignatureDescriptionPointsSeverity
UA changed for same IPMultiple User-Agents — bot rotation technique+25
Burst: 6 req / 2sAbnormally fast request rate — automated scanning+35
Foreign referer seenReferer from unrelated external domain+10
Σ = 70
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

2026-05-11 08:00:07
First malicious request detected
IP entered monitoring from server access logs
During observation
Multiple detection signatures triggered
UA changed for same IP (+25), Burst: 6 req / 2s (+35), Foreign referer seen (+10)
2026-05-11 08:00:07
Last malicious request observed
Total score reached: 70/100
Next cycle
IP blocked — all subsequent requests denied (HTTP 403)
Added to blocklist automatically
05

Network Provider

CenturyLink Communications
AS3356 · 🇺🇸 United States
06

Recommendations

Actions taken & recommended

  • IP 205.169.39.138 is blocked at application level (HTTP 403)
  • Consider blocking at firewall level (iptables/CSF) to reduce server load
  • Other malicious IPs detected in the same /24 subnet — consider blocking 205.169.39.0/24
  • 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 205.169.39.138 shows suspicious UA behavior. Block empty User-Agent requests. Implement JavaScript-based bot detection for sensitive endpoints.

🌊 Traffic Flood Defense

IP 205.169.39.138 is generating excessive traffic. Limit connections per source IP. Enable geographic blocking if traffic from this region is unexpected.

07

Neighbors in 205.169.39.0/24

Other blocked IPs from the same /24 subnet — indicates systematic abuse from this network range.

09

Blacklist Status (DNSBL)

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

⛔ LISTED
zen.spamhaus.org
✓ Clean
ix.dnsbl.manitu.net
✓ Clean
bl.spamcop.net
✓ Clean
dnsbl.sorbs.net
✓ Clean
dnsbl-1.uceprotect.net
✓ Clean
b.barracudacentral.org
✓ Clean
truncate.gbudb.net
✓ Clean
psbl.surriel.com

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

10

Threat Analysis

205.169.39.138 has been assigned a threat score of 70/100 (High). This score indicates high threat severity. The IP has shown clear patterns of malicious behavior that warrant immediate defensive measures.

The following attack categories were identified:

User-Agent AnomalyRequest Flooding

📊 Threat Analysis

The address 205.169.39.138 originates from Santa Clara, United States, operating on the network of CenturyLink Communications. It was identified through automated analysis of incoming network traffic across monitored endpoints. During its 1-day observation window, we recorded 1 hostile requests from this IP — roughly 1 per day on average. This is a residential IP address, suggesting a compromised home device such as a router, smart appliance, or infected workstation participating in a botnet. Two attack patterns were identified (User-Agent Anomaly and Request Flooding), suggesting a semi-automated campaign that targets multiple vulnerabilities. With 172 flagged addresses, United States represents a significant presence in our threat database. The score of 70/100 indicates a confirmed malicious actor. Network-level blocking is appropriate.

This IP is classified as residential, suggesting it may belong to a compromised home device, IoT botnet member, or an infected personal computer. Residential IPs involved in attacks often indicate malware infection without the owner's knowledge.

11

Related Threats

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🏢 Same network: AS3356

205.169.39.217 (155)205.169.39.128 (155)205.169.39.71 (155)205.169.39.103 (145)205.169.39.149 (145)View all →
12

Security Intelligence

💡 HTTP Header Analysis for Threat Detection

Examining HTTP headers beyond User-Agent reveals attack tools and automated scripts. Missing standard headers, unusual ordering, non-standard values, and inconsistencies with claimed client identity all serve as reliable detection signals.

💡 Autonomous System Analysis

Analyzing attack patterns at the AS (Autonomous System) level reveals which networks harbor the most malicious activity. Some ASes have abuse rates orders of magnitude higher than average, indicating lax enforcement of acceptable use policies.

🔍 Check Any IP Address

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