New findings from Cyble Research and Intelligence Labs (CRIL) analyzed nearly 20 actively maintained repositories and found rapid technical progression continuing through late 2025 and into 2026. These tools have moved beyond basic terminal scripts. They now include cross-platform desktop applications, Telegram-integrated automation frameworks, and high-performance systems capable of launching large-scale SMS, OTP, and voice-bombing campaigns across multiple geographies.
Researchers emphasize that the study reflects patterns within a defined research sample and should be viewed as indicative trends rather than a full mapping of the global ecosystem. Even within that limited dataset, the scale and sophistication are significant
SMS and OTP bombing campaigns exploit legitimate authentication endpoints. Attackers repeatedly trigger password resets, registration verifications, or login challenges, overwhelming a victim’s phone with genuine SMS messages or automated voice calls. The result ranges from harassment and disruption to more serious risks such as MFA fatigue.
Across the 20 repositories examined, researchers identified approximately 843 vulnerable API endpoints. These endpoints belonged to organizations across telecommunications, financial services, e-commerce, ride-hailing services, and government platforms. The recurring weaknesses were predictable: inadequate rate limiting, weak or poorly enforced CAPTCHA mechanisms, or both.
Regional targeting was uneven. Roughly 61.68% of observed endpoints—about 520—were linked to infrastructure in Iran. India accounted for 16.96%, approximately 143 endpoints. Additional activity was concentrated in Turkey, Ukraine, and parts of Eastern Europe and South Asia.
The attack lifecycle typically begins with endpoint discovery. Threat actors manually test authentication workflows, probe common API paths such as /api/send-otp or /auth/send-code, reverse-engineer mobile applications to uncover hardcoded API references, or leverage community-maintained endpoint lists shared in public repositories and forums. Once identified, these endpoints are integrated into multi-threaded attack frameworks capable of issuing simultaneous requests at scale.
The technical sophistication of SMS and OTP bombing tools has advanced considerably. Maintainers now offer versions across seven programming languages and frameworks, lowering entry barriers for individuals with limited coding expertise.
Modern toolkits commonly include:
- Multi-threading to enable parallel API exploitation
- Proxy rotation to bypass IP-based defenses
- Request randomization to mimic human behavior
- Automated retry mechanisms and failure handling
- Real-time activity dashboards
More concerning is the widespread use of SSL bypass techniques. Approximately 75% of the repositories analyzed disable SSL certificate validation. Instead of relying on properly verified secure connections, these tools deliberately ignore certificate errors, enabling traffic interception or manipulation without interruption. SSL bypass has emerged as one of the most frequently observed evasion strategies.
In addition, 58.3% of repositories randomize User-Agent headers to evade signature-based detection systems. Around 33% exploit static or hardcoded reCAPTCHA tokens, effectively bypassing poorly implemented bot protections.
The ecosystem has also expanded beyond SMS flooding. Voice-bombing capabilities—automated call floods triggered through telephony APIs—are now integrated into several frameworks, broadening the harassment surface.
Commercialization and Data Harvesting Risks
Alongside open-source development, a commercial layer has surfaced. Browser-based SMS and OTP bombing platforms now offer simplified, point-and-click interfaces. Often marketed misleadingly as “prank tools” or “SMS testing services,” these platforms eliminate technical setup requirements.
Unlike repository-based tools that require local execution and configuration, web-based services abstract proxy management, API integration, and automation processes. This significantly increases accessibility.
However, these services frequently operate on a dual-threat model. Phone numbers entered into such platforms are often harvested. The collected data may later be reused in spam campaigns, sold as lead lists, or integrated into broader fraud operations. In effect, users risk exposing both their targets and themselves to ongoing exploitation.
Financial, Operational, and Reputational Impact
For individuals, SMS and OTP bombing can severely disrupt device usability. Effects include degraded performance, overwhelmed message inboxes, exhausted SMS storage, battery drain, and increased risk of MFA fatigue—potentially leading to accidental approval of malicious login attempts. Voice-bombing campaigns further intensify the disruption.
For organizations, the consequences extend well beyond inconvenience.
Financially, each OTP message typically costs between $0.05 and $0.20. An attack generating 10,000 messages can result in expenses ranging from $500 to $2,000. Sustained abuse of exposed endpoints can drive monthly SMS costs into five-figure sums.
Operationally, legitimate users may be unable to receive verification codes, customer support volumes can surge, and authentication delays can impact service reliability. In regulated industries, failure to secure authentication workflows may introduce compliance risks.
Reputational damage compounds these issues. Users quickly associate spam-like behavior with weak security controls, eroding trust and confidence in affected organizations.
As SMS and OTP bombing tools continue to evolve in sophistication and accessibility, the strain on authentication infrastructure underscores the urgent need for stronger rate limiting, adaptive bot detection, and hardened API protections across industries
