CVE-2024-38537 Inclusion of Untrusted polyfill.io Code Vulnerability in fides.js
Attackers could execute malicious code on legacy browsers via compromised polyfill.io dependency in Fides consent script.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-38537?
CVE-2024-38537 is a vulnerability in ethyca fides, published on 2 Jul 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Fides is an open-source privacy engineering platform. `fides.js`, a client-side script used to interact with the consent management features of Fides, used the `polyfill.io` domain in a very limited edge case, when it detected a legacy browser such as IE11 that did not support the fetch standard. Therefore it was possible for users of legacy, pre-2017 browsers who navigate to a page serving `fides.js` to download and execute malicious scripts from the `polyfill.io` domain when the domain was compromised and serving malware. No exploitation of `fides.js` via `polyfill.io` has been identified as of time of publication.
The vulnerability has been patched in Fides version `2.39.1`. Users are advised to upgrade to this version or later to secure their systems against this threat. On Thursday, June 27, 2024, Cloudflare and Namecheap intervened at a domain level to ensure `polyfill.io` and its subdomains could not resolve to the compromised service, rendering this vulnerability unexploitable. Prior to the domain level intervention, there were no server-side workarounds and the confidentiality, integrity, and availability impacts of this vulnerability were high. Clients could ensure they were not affected by using a modern browser that supported the fetch standard.
Weakness: CWE-829
Which versions are affected by CVE-2024-38537?
3 open source packages ship an affected version, including ethyca-fides. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
ethyca-fides PyPI | All versions | 2.39.1 |
ethyca-fides PyPI | All versions | 2.39.1 |
ethyca-fides PyPI | All versions | 2.39.1 |
Products include Ethyca Fides.
How do I fix CVE-2024-38537?
Upgrade ethyca-fides to 2.39.1 or later.
Is CVE-2024-38537 being exploited?
There is no known exploitation of CVE-2024-38537 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in ethyca fides
- CVE-2024-45053 Remote Code Execution Vulnerability via SSTI in Fides Webserver Jinja Email Templating Engine
- CVE-2023-41319 Remote Code Execution in Custom Integration Upload in Fides
- CVE-2025-57817 Fides Webserver API is Vulnerable to OAuth Client Privilege Escalation
- CVE-2023-48224 Cryptographically Weak Generation of One-Time Codes for Identity Verification in ethyca-fides
- CVE-2023-46124 Server-Side Request Forgery Vulnerability in Custom Integration Upload
Sources
Also known as GHSA-cvw4-c69g-7v7m, PYSEC-2026-1339.