Thursday , April 24 2025
coding

New report; Polyfill[.]io Attack Impacts Over 380,000 Hosts

The web development community was affected by a supply chain attack on the popular Polyfill.io JavaScript library last week. Polyfill.js supports modern tools on older web browsers for cross-compatibility.

In February 2024, the Polyfill.io domain and GitHub account were acquired by Funnull, a Chinese CDN company. This raised concerns about the service’s legitimacy. Malware injected through cdn.polyfill.io has been redirecting users to malicious sites, affecting over 100,000 websites, including high-profile platforms like JSTOR, Intuit, and the World Economic Forum. The malware is sophisticated and hard to detect and combat, using different evasion techniques.

SonicWall patched SSLVPN Vuln Allowing Firewall Crashing

SonicWall has revealed a vulnerability in its SonicOS SSLVPN Virtual Office interface that could let remote attackers crash firewall appliances....
Read More
SonicWall patched SSLVPN Vuln Allowing Firewall Crashing

GitLab Releases Security Update For Multiple Vulns

GitLab has announced a security advisory urging users to upgrade their self-managed installations right away. Versions 17.11.1, 17.10.5, and 17.9.7...
Read More
GitLab Releases Security Update For Multiple Vulns

ISPAB president “whatsapp” got hacked via phishing link

Imdadul Haque, the president of Internet Service Provider of Bangladesh (ISPAB) said, I automatically got back my WhatsApp account. What...
Read More
ISPAB president “whatsapp” got hacked via phishing link

Zyxel released patches 2 vulns in its USG FLEX H series firewalls

Zyxel Networks has issued critical security patches for two high-severity vulnerabilities in its USG FLEX H series firewalls. These flaws...
Read More
Zyxel released patches 2 vulns in its USG FLEX H series firewalls

South Korea’s largest SK Telecom Hit by Malware: SIM-related info leaked

South Korea's largest mobile operator, SK Telecom, is warning that a malware infection allowed threat actors to access sensitive USIM-related...
Read More
South Korea’s largest SK Telecom Hit by Malware: SIM-related info leaked

ChatGPT Develops Exploit for CVEs Before Public PoCs Share

Security researcher Matt Keeley showed that artificial intelligence can now develop working exploits for critical vulnerabilities before public proof-of-concept (PoC)...
Read More
ChatGPT Develops Exploit for CVEs Before Public PoCs Share

TP-Link Router Vulns Allow to Execute Malicious SQL Commands

Several vulnerabilities have been found in TP-Link routers, exposing users to serious security risks from SQL injection flaws in their...
Read More
TP-Link Router Vulns Allow to Execute Malicious SQL Commands

SSL.com’s domain validation system’s bug found: Hacker exploited

SSL.com has revealed a major security flaw in its domain validation system, which could enable attackers to acquire fake SSL...
Read More
SSL.com’s domain validation system’s bug found: Hacker exploited

Amazon Follows Microsoft’s Lead, Halts Some Data Center Deals

Amazon has paused some data center lease negotiations for its cloud division, particularly in international markets, according to Wells Fargo...
Read More
Amazon Follows Microsoft’s Lead, Halts Some Data Center Deals

Hackers Exploit Zoom’s Remote Control Feature for System Access

ELUSIVE COMET is a threat actor conducting a sophisticated attack campaign that uses Zoom's remote control feature to access victims'...
Read More
Hackers Exploit Zoom’s Remote Control Feature for System Access

Several companies have reacted to this situation. Cloudflare and Fastly provided secure alternative endpoints for users. Google stopped displaying ads for e-commerce sites using Polyfill.io. The uBlock Origin website blocker added the domain to its filter list. Andrew Betts, the creator of Polyfill.io, advised website owners to remove the library as it is no longer needed for modern browsers.

On June 27, Namecheap, the domain registrar for polyfill.io, took down the harmful domain, which reduces the immediate threat.

Latest report indicates, Censys has identified a significant number of web hosts using the polyfill.io CDN. As of the latest data, 384,773 hosts were found to include references to “https://cdn.polyfill[.]io” or “https://cdn.polyfill[.]com” in their HTTP responses.

  All are hosted in AS139057, LDPL-AS-AP LEGEND DYNASTY PTE. LTD.

A notable concentration of these hosts, approximately 237,700, are located within the Hetzner network (AS24940), primarily in Germany. This is not surprising – Hetzner is a popular web hosting service, and many website developers leverage it.

Domains tied to major companies like Warner Bros, Hulu, Mercedes-Benz, and Pearson have many hosts referring to a malicious polyfill endpoint. The most common hostname associated with hosts presenting the endpoint is ns-static-assets.s3.amazonaws.com, which suggests widespread usage among Amazon S3 static website hosting users.

The website “www.feedthefuture.gov” appears in these top results. This shows that polyfill.io is used in many sectors, including government websites. Censys found 182 affected hosts with a “.gov” domain.

View the following report breaking down hostnames on sites using this endpoint.
Estimates of affected websites vary widely, but it’s clear that this supply chain attack has had a widespread impact. Sansec reported 100,000 affected websites, while Cloudflare suggested “tens of millions”.

Cloudflare and Fastly made new secure options to help users stay safe without breaking websites. Censys found 216,504 hosts using these new options, up from 80,312 last Friday, June 28th.

Check Also

ransomware

Bengaluru firm got ransomware attack, Hacker demanded $70,000

Bengaluru’s Whiteboard Technologies Pvt Ltd was hit by a ransomware attack, with hackers demanding a …

Leave a Reply

Your email address will not be published. Required fields are marked *