# Polyfill.io: how AI models rank it, November 2026

Gane Index, November 2026 Edition. Named in 4 judge labels across 1 category by 4 of 14 models. Page: https://www.gane.ai/index/it/vendors/polyfill-io

## Standing by category

| Category | Share | Rank | Negative rate | Labels |
|---|---|---|---|---|
| [Content delivery networks](https://www.gane.ai/index/it/network/content-delivery-networks/index.md) | 0% | 58 | 100% | 4 |

## And against it

- "caught injecting malicious code into responses. If you are using cdn.polyfill.io, you should immediately remove it" (Mistral Small, CDN)
- "In mid-2024, this popular CDN suffered a major supply chain attack after its domain changed ownership." (Qwen 3.7 Flash, CDN)
- "The most dangerous recent example... turned into a malware CDN" (Kimi K2, CDN)
- "polyfill.io / cdn.polyfill.io — AVOID ENTIRELY" (DeepSeek V4 Flash, CDN)

## By model

| Model | First choice | Alternative | Mention | Warning | Labels |
|---|---|---|---|---|---|
| Claude Haiku 4.5 | 0 | 0 | 0 | 0 | 0 |
| GPT-5.4 mini | 0 | 0 | 0 | 0 | 0 |
| Gemini 3.5 Flash | 0 | 0 | 0 | 0 | 0 |
| Perplexity Sonar | 0 | 0 | 0 | 0 | 0 |
| Grok 4.20 | 0 | 0 | 0 | 0 | 0 |
| Mistral Small | 0 | 0 | 0 | 1 | 1 |
| DeepSeek V4 Flash | 0 | 0 | 0 | 1 | 1 |
| Llama 4 Maverick | 0 | 0 | 0 | 0 | 0 |
| Qwen 3.7 Flash | 0 | 0 | 0 | 1 | 1 |
| Kimi K2 | 0 | 0 | 0 | 1 | 1 |
| GLM 4.7 FlashX | 0 | 0 | 0 | 0 | 0 |
| MiniMax M2.5 | 0 | 0 | 0 | 0 | 0 |
| GPT-6 Luna | 0 | 0 | 0 | 0 | 0 |
| Muse Glimmer 30B | 0 | 0 | 0 | 0 | 0 |

## Sources returned with these answers

The sites and pages cited by the answers that named Polyfill.io, from 4 of the 4 answers that named it (only the models that return a source list).

### Domains cited

- dl.acm.org: 3
- github.com: 3
- httptoolkit.com: 3
- fastly.com: 2
- rdi.berkeley.edu: 2
- addons.opera.com: 1
- agid.gov.it: 1
- antropy.co.uk: 1
- arp242.net: 1
- arxiv.org: 1

### Pages cited

- https://httptoolkit.com/blog/public-cdn-risks: 3
- https://dl.acm.org/doi/full/10.1145/3499428: 2
- https://github.com/httptoolkit/httptoolkit-website/blob/main/src/content/posts/public-cdn-risks.mdx: 2
- https://rdi.berkeley.edu/blog/polyfill: 2
- https://addons.opera.com/en/extensions/details/retirejs: 1
- https://agid.gov.it/en/news/polyfillio-cert-agid-advises-public-administrations-quickly-remove-it-their-sites-0: 1
- https://antropy.co.uk/blog/all-sites-go-down-major-website-outages-last-five-years: 1
- https://arp242.net/cdn.html: 1

## Record

- Method: https://www.gane.ai/index/it/methodology
- License: CC BY 4.0. Cite as Gane Index, November 2026 Edition, www.gane.ai/index/it.