Does Adblock Stop Crypto Mining Scripts? How Browser…

KEY TAKEAWAYS

1. AdBlock includes a cryptocurrency mining protection filter list enabled by default that blocks known cryptojacking scripts without requiring manual configuration.
2. SonicWall recorded 1.06 billion cryptojacking hits in 2023, a 659% increase over 2022.
3. Security researchers at c/side discovered 3,500 websites hijacked with stealth JavaScript miners using WebSocket connections in July 2025.
4. Dedicated extensions like MinerBlock target crypto mining scripts specifically, while NoCoin is a discontinued tool that was archived in 2020.
5. Google found 86% of compromised cloud instances were used for cryptocurrency mining, while attackers deployed miners within 22 seconds of gaining access in 58% of cases.

  Cryptojacking attacks surged past one billion recorded hits in 2023. Attackers inject hidden JavaScript into websites that force visitors' devices to mine cryptocurrency without consent. Browser extensions remain one of the most accessible defenses against these scripts.Ad blockers like AdBlock and uBlock Origin include built-in protections against known mining scripts. Specialized tools like MinerBlock focus exclusively on detecting and blocking crypto mining code. This article examines how each extension type works, its limitations, and which threats still bypass standard browser protections.

How AdBlock and uBlock Origin Handle Crypto Mining Scripts

AdBlock ships with a "Cryptocurrency Mining Protection List" enabled by default upon installation, requiring no manual configuration from users. The filter list identifies and blocks domains and scripts associated with browser-based mining operations. AdBlock has confirmed successful blocks on high-profile sites, including The Pirate Bay and Showtime properties that ran unauthorized miners.uBlock Origin works as a full extension on Firefox and Brave, while Chrome users can use the reduced uBlock Origin Lite version following Chrome's transition away from Manifest V2. Its default filter lists cover major mining domains, and users can enable the dedicated "Resource Abuse" filter list for expanded coverage.The extension blocks network requests to known mining pools and script hosting domains before they execute in the browser.Both extensions rely on regularly updated blocklists maintained by community contributors and security researchers. When a new mining domain appears, it must be identified, reported, and added to the list before the extension blocks it. This creates a detection gap between when a new cryptojacking script deploys and when blocklist maintainers catalog it.General ad blockers effectively stop known, cataloged mining scripts that load from identifiable domains. They serve as a strong first layer of defense for casual internet users who want protection without installing multiple extensions. Advanced mining techniques that obfuscate code or use dynamic connections require more specialized detection methods.

Dedicated Anti-Mining Extensions Target What Ad Blockers Miss

MinerBlock, an open source browser extension available on GitHub, uses two detection methods simultaneously to catch mining scripts. The first method blocks requests and scripts loaded from a curated blacklist of known mining domains and endpoints. The second method detects CoinHive-style mining behavior within loaded scripts regardless of the hosting domain.Running a dedicated anti-mining extension alongside a general ad blocker provides layered protection. The ad blocker handles known domains and advertising-injected miners, while the specialized extension catches scripts using code-level behavioral patterns. This combination addresses the widest range of cryptojacking techniques currently deployed across the web.

Modern Cryptojacking Attacks Outpace Basic Browser Protections

Security researcher Himanshu Anand at c/side discovered in July 2025 that attackers had compromised over 3,500 websites with stealth JavaScript miners, according to The Hacker News. The miners used WebSocket connections to fetch tasks dynamically from external servers, adjusting mining intensity based on each device's computational power.Anand described the attack as "a stealth miner, designed to avoid detection by staying below the radar of both users and security tools." The infrastructure hosting the mining JavaScript was linked to Magecart credit card skimmers, showing that attackers diversified payloads across cryptojacking and financial data theft. c/side researchers noted that "Attackers now prioritize stealth over brute-force resource theft."SonicWall Capture Labs recorded 1.06 billion cryptojacking hits globally in 2023, representing a 659% increase over the 139.3 million hits recorded in 2022. A single month in May 2023 reached 77.6 million hits, exceeding total annual figures from 2018 and 2019 combined. According to CoinLaw's 2026 statistics report, the anti-cryptojacking solutions market is projected to reach $31.8 billion by 2030.Sysdig research quantified the cost asymmetry of cryptojacking, finding that attackers earn approximately $1 for every $53 a victim pays in cloud compute fees. A TeamTNT case study showed $8,100 in mined cryptocurrency against $430,000 in victim cloud bills. Browser-based attacks follow a similar model, consuming electricity and hardware resources disproportionate to the mining output generated.

Practical Steps to Maximize Browser-Level Cryptojacking Defense

Installing one general ad blocker alongside one dedicated mining extension can provide layered browser-level protection. AdBlock or uBlock Origin on supported browsers, or uBlock Origin Lite on Chrome, handles known threats through maintained filter lists. MinerBlock can add another layer of protection against mining scripts.Keeping extensions updated is critical because new mining domains and obfuscation techniques appear continuously. Most extensions update filter lists automatically, but users should verify that automatic updates remain enabled in browser extension settings. Google's analysis found that 86% of compromised cloud instances were deployed for mining, with miners deployed within 22 seconds of access in 58% of cases.Disabling JavaScript entirely prevents all browser-based mining but breaks most modern websites. A more practical approach uses browser developer tools to monitor CPU usage spikes while visiting unfamiliar sites. Sustained high CPU usage during normal browsing can indicate unauthorized script activity that extensions may not have caught.Enterprise users should combine browser extensions with endpoint detection and response solutions for comprehensive protection. The average breach goes undetected for 277 days, according to SentinelOne. Browser extensions stop the initial script injection, while EDR platforms detect persistence mechanisms that survive browser session termination.

Regulatory Implications

Cryptojacking remains a criminal offense in most jurisdictions under computer fraud and unauthorized access statutes. The U.S. Computer Fraud and Abuse Act and the U.K. Computer Misuse Act cover unauthorized use of computing resources for mining. Global information security spending is forecast to reach $240 billion in 2026, according to Gartner.

What's Next?

Firefox has blocked known cryptominers by default since 2019 through its Enhanced Tracking Protection. WebAssembly based miners present the next frontier of evasion, operating at near native speeds that behavioral detection must adapt to match. According to CoinLaw, the anti-cryptojacking solutions market is projected to reach $31.8 billion by 2030.

FAQs

Does AdBlock automatically block crypto mining scripts in the browser? AdBlock includes a Cryptocurrency Mining Protection List enabled by default that blocks known cryptojacking scripts without requiring any manual configuration from users. Is uBlock Origin effective against browser-based cryptojacking attacks? uBlock Origin blocks major mining domains through default filters and offers a dedicated Resource Abuse list for expanded cryptojacking protection in browser settings. What is MinerBlock, and how does it differ from standard ad blockers? MinerBlock is an open source extension that uses domain blacklists and behavioral detection to target crypto mining scripts. Can cryptojacking scripts still bypass browser extensions in 2026? Advanced miners using WebSocket connections, code obfuscation, and dynamic payload delivery can evade blocklist-based detection before researchers identify and catalog the infrastructure involved. How much does cryptojacking cost victims compared to the attacker's profit? Sysdig research found attackers earn roughly one dollar for every fifty-three dollars victims pay in stolen computing resources and inflated electricity costs. Should users install multiple browser extensions to block cryptojacking scripts? Combining one general ad blocker with one dedicated mining extension such as MinerBlock provides layered defense covering known and potentially behavior-based threats. What are the warning signs that a website is running a crypto miner? Sudden sustained high CPU usage, increased fan noise, sluggish browser performance, and elevated battery drain on laptops can indicate unauthorized crypto mining activity.

References

1. AdBlock Cryptocurrency Mining Protection, getadblock.com
2. 3,500 Websites Hijacked with Stealth JavaScript Miners, The Hacker News
3. Cryptojacking Statistics 2026, CoinLaw
4. MinerBlock: Browser Extension for Blocking Cryptocurrency Miners, GitHub