CVE-2024-38537

NONE

Fides < 2.39.1 - Untrusted Script Execution via polyfill.io Dependency

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2024-38537. PoCs published by Havoc10-sw.

AI-analyzed exploit summary The repository contains a Python script that scans for the presence of 'polyfill.io' in the Content Security Policy (CSP) headers of given URLs. It does not exploit CVE-2024-38537 but detects potential exposure to the vulnerability.

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.

Exploits (1)

nomisec SCANNER
by Havoc10-sw · poc
https://github.com/Havoc10-sw/Detect_polyfill_CVE-2024-38537-

The repository contains a Python script that scans for the presence of 'polyfill.io' in the Content Security Policy (CSP) headers of given URLs. It does not exploit CVE-2024-38537 but detects potential exposure to the vulnerability.

Classification
Scanner 95%
Attack Type
Info Leak
Complexity
Trivial
Reliability
Reliable
Target: Web applications using CSP headers
No auth needed
Prerequisites: List of target URLs in a file (urls.txt)
devstral-2 · analyzed Feb 18, 2026 Full analysis →

References (5)

Core 5

Scores

CVSS v3 0.0
EPSS 0.2223
EPSS Percentile 95.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-829
Status published
Products (2)
ethyca/fides < 2.39.1
pypi/ethyca-fides 0 - 2.39.1PyPI
Published Jul 02, 2024
Tracked Since Feb 18, 2026