SMS remains a vital communication channel, but fraud undermines subscriber trust, degrades their user experience, and reduces customer loyalty. At the same time, fraudsters target the operator's network itself—attacks like SMS flooding can cause service disruptions and financial losses. In this article, we’ll examine the main types of fraud text message, their impact, and how an SMS firewall mitigates these threats.
 

Main Types of SMS Fraud and Their Impact

Fraudsters typically use one of four text message scam tactics. These schemes harm both subscribers and mobile operators.

Spam Campaigns  

These are mass unsolicited messages sent rapidly across subscriber bases, eroding trust in SMS as a communication channel. As effectiveness declines, advertisers see diminishing returns, which directly reduces operator revenue and weakens interest from corporate clients in using SMS for outreach. Spam also leads to a spike in subscriber complaints and can eventually drive customer churn. For example, in February 2025 alone, Americans received 19.2 billion spam messages.

SMS Spoofing  

Spoofing the sender allows fraudsters to send fake text scam on behalf of trusted brands—banks, online services, and government agencies. These messages often contain malicious links or software, leading recipients to compromise sensitive data, lose money, and ultimately lose trust in the companies whose names were impersonated.

In 2024, for instance, scammers sent messages to Americans claiming to be from the U.S. Postal Service, warning of delivery issues. The included link led to a fake USPS website, where users entered credit card details and Social Security numbers.

SMS Flooding  

This is a direct attack on the operator’s network. Attackers generate thousands of SMS messages per second, overwhelming the infrastructure. The consequences include service outages, increased costs for incident response, and revenue loss. In severe cases, the overload can trigger a wave of complaints and the defection of corporate clients who depend on consistent service quality.

URL Phishing  

These messages contain fake links that redirect users to phishing websites, where sensitive data like passwords and card details are stolen. Each incident damages the operator’s reputation.

In spring 2025, the U.S. experienced a wave of phishing attacks. Subscribers received SMS alerts about unpaid parking fines with a link to settle the debt. Clicking the link led to a fake payment portal, resulting in stolen funds and personal data, including banking information.

We identified more than 1,000 phishing scam text messages on the Zain Kuwait network before deploying a URL scanner—a module within the EW SMS Firewall solution. Now, such messages are automatically blocked.

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Business Impact of Fraud Text Messages

The scale and recurrence of attacks turn what starts as a technical threat into a direct source of financial losses for mobile operators.

 — Declining ad campaign performance. Subscribers stop opening messages and begin ignoring even legitimate SMS promotions

 — Increased churn. Operator reputation suffers, prompting subscribers to switch to competitors with stronger network security

 — Revenue loss. Businesses stop using operator services when SMS campaigns fail to reach or engage target audiences

Next, we'll look at how fraudsters manage to bypass operator security systems to send text message scams.


Losses from SMS Fraud in the U.S. in 2023  
Source: 17 Spam Text Statistics for 2025 & Spam Text Messages Examples (SlickText)
 

Why Traditional Protection Methods Fail to Stop SMS Fraud

For years, mobile operators relied on filtering at the SMS center (SMSC) level. This approach is based on static rules—blocking specific numbers, number ranges, or known message templates. While it may seem effective at first, its performance quickly deteriorates in practice.


Source: Commercial Anti-Smishing Tools and Their Comparative Effectiveness Against Modern Threats (Cornell University)

Scammers can easily bypass traditional defenses by changing sender addresses or slightly altering message content. Each new attack method requires manual rule updates, turning protection into a constant race in which the operator is always one step behind. Meanwhile, network load increases and response times get longer.

To truly protect subscribers and preserve their reputation, operators need dynamic tools capable of real-time traffic analysis and monitoring. This is exactly what an SMS firewall provides.
 

How an SMS Firewall Protects Against Fraud

A modern SMS firewall addresses a critical challenge for mobile operators—ensuring transparency and control over all messages transmitted through the network. This not only reduces fraud risk but also helps operators meet regulatory requirements for telecom infrastructure security.

The SMS firewall works by analyzing all SMS traffic across multiple parameters:

— Source: The system verifies sender identifiers for both P2P and A2P messages  

— Content: The firewall scans message text for suspicious keywords, phrases, templates, and links  

— Sending frequency: It can detect an attack at the outset and block it instantly  

— Correlation with known fraud patterns


For example, EW SMS Firewall analyzes SMS traffic using more than 20 parameters

Unlike static SMSC-level filters, an SMS firewall uses dynamic rules that are updated in two ways:

— Manually—by managed services specialists who continuously monitor traffic for attack indicators and emerging fraud schemes  

— Automatically—through an AI module that learns on the fly and updates filtering rules and blacklists in real time

As a result:  

— The SMS firewall blocks fraud text messages before they even enter the network
  
— Network load is reduced and SMS flooding attacks are prevented  

— Subscribers receive only legitimate messages, boosting their trust in the SMS channel  

— The operator demonstrates compliance with regulatory requirements and maintains a strong reputation

The SMS firewall becomes a strategic layer of defense—eliminating the vulnerabilities of traditional methods and helping the operator protect its most valuable assets: revenue, customers, and market trust.

Let’s compare SMSC-level protection with the capabilities of an SMS firewall.
 

Criterion	SMS Center	SMS Firewall
Operating Principle	Static rules and blocking of known numbers and templates.	Dynamic analysis of all SMS traffic with real-time rule updates.
Protection Against New Fraud Schemes	No: fraudsters bypass filters using new numbers and schemes.	Yes: identifies even zero-day attacks using an AI module, heuristic analysis, and monitoring by managed services specialists.
Response Speed	Manual rule updates required—slow response.	Automatic rule updates and nonstop monitoring.
Types of Threats	Partial protection against basic spam.	Blocks spam, SMS spoofing, SMS flooding, URL phishing, and other types of threats.
Network Load	Risk of overload during SMS flooding.	Timely detection and blocking of attacks reduce network load.
Impact on Subscriber Loyalty	Subscribers receive fraud text messages, and trust in the communication channel declines.	Subscribers receive only legitimate messages, keeping the channel reliable.

Comprehensive Protection of Telecom Operators’ SMS Traffic: 5 Signs of an Effective SMS Firewall
 

Business Impact of Network Protection

For a mobile operator, deploying an SMS firewall is not just a matter of technical security—it is a strategic business investment.

— Fewer subscriber complaints and higher profits. When users stop receiving spam and phishing scam text messages, their trust in the channel is restored. Loyalty increases, churn decreases, and retaining customers is 25 times cheaper than acquiring new ones;  

— Reduced financial losses. Blocking SMS flooding protects infrastructure from overloads and downtime. This directly lowers outage-related losses and eliminates extra costs for network recovery;  

— Stronger reputation. An operator that ensures channel security is seen as a reliable partner. This is critical when working with SMS aggregators, content providers, and enterprise clients.

One of Eastwind’s clients is an international SMS aggregator. Before entering a new market, it secures the mobile operator’s network through which traffic will be routed. This ensures subscriber loyalty, campaign effectiveness, and revenue from A2P traffic.

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SMS fraud is no longer just a subscriber-level issue. For operators, it poses the risk of customer churn, financial losses, and reputational damage. An effective solution is the SMS firewall. It provides transparency and control over all SMS traffic, blocks attacks in real time, protects subscribers, enhances their loyalty, and preserves market trust.

Learn more about the capabilities of EW SMS Firewall