ABUSE.MOM
THREAT REPORT

IP Threat Report
138.99.81.1

ABUSE.MOM — BEHAVE OR GET EXPOSED

Generated: 2026-05-27 06:54:47
First seen: 2026-03-20 09:00:06
Last seen: 2026-03-20 09:00:06
103

⛔ Verdict: BLOCK

This IP address has been classified as a source of malicious automated activity. Threat score: 103/100. Total malicious requests observed: 1.

DANGER_PATHMETHOD
01

Geolocation & Classification

IP Address
138.99.81.1
Type
Residential
Country
🇧🇷 Brazil
City
Cabo Frio
ISP
MaxNet Telecom
Organization
Seven NET Telecom Ltda
Autonomous System
AS271596 MaxNet Telecom
Hit Count
1
02

Detection Signatures

SignatureDescriptionPointsSeverity
Danger strong hits: 3High-risk paths: shells, RCE vectors, exploits+75
Danger medium hits: 2Medium-risk: admin panels, config files+20
POST requests presentBehavioral anomaly detected by automated analysis+8
Σ = 103
03

Observed Activity

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

[redacted]
GET
/
200
Requests shown: 1 · HTTP 404: 0 · Dangerous patterns: 0

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

04

Timeline

2026-03-20 09:00:06
First malicious request detected
IP entered monitoring from server access logs
During observation
Multiple detection signatures triggered
Danger strong hits: 3 (+75), Danger medium hits: 2 (+20), POST requests present (+8)
2026-03-20 09:00:06
Last malicious request observed
Total score reached: 103/100
Next cycle
IP blocked — all subsequent requests denied (HTTP 403)
Added to blocklist automatically
05

Network Provider

MaxNet Telecom
AS271596 · 🇧🇷 Brazil
06

Recommendations

Actions taken & recommended

  • IP 138.99.81.1 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 138.99.81.0/24
  • Report abuse to the network provider via their abuse contact
  • Ensure sensitive files (.env, .git, backups) are not accessible from the web

⚙️ Defensive Recommendations

Block 138.99.81.1 at the network perimeter. Implement defense-in-depth combining IP blocking with application-layer protections.

07

Neighbors in 138.99.81.0/24

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

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

10

Threat Analysis

138.99.81.1 has been assigned a threat score of 103/100 (Critical). A score this high marks a critical threat actor. This address has demonstrated persistent, aggressive malicious behavior across multiple detection vectors.

📊 Threat Analysis

Network traffic from 138.99.81.1, located in Cabo Frio, Brazil, operating on the network of MaxNet Telecom, has been classified as malicious by our automated threat scoring engine. Our sensors captured 1 malicious requests from this address across a 1-day span, reflecting a sustained attack cadence of ~1 requests per day. This is a residential IP address, suggesting a compromised home device such as a router, smart appliance, or infected workstation participating in a botnet. Brazil currently accounts for 103 blocked IPs in our database, making it a significant source of malicious traffic. At 103/100, this is an extremely high-risk address. All traffic should be considered hostile.

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

🇧🇷 Top threats from Brazil

173.245.211.6 (293)20.206.78.203 (283)20.197.194.128 (280)20.197.233.108 (280)20.226.83.230 (280)View all →

🏢 Same network: AS271596

138.99.81.2 (68)138.99.81.3 (68)View all →
12

Security Intelligence

💡 Brute Force Attack Mechanics

Brute force attacks systematically try username and password combinations to gain unauthorized access. Modern attacks leverage credential databases from previous breaches, testing millions of combinations using distributed botnets across multiple IP addresses.

💡 Insider Threat Indicators

Insider threats — whether malicious or negligent — account for a significant percentage of data breaches. Behavioral analytics detecting unusual access patterns, data downloads, and privilege escalation help identify insider risks before damage occurs.

🔍 Check Any IP Address

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