Improper Certificate Validation Affecting libcurl package, versions [8.8.0,8.15.0)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-CONAN-LIBCURL-11499918
- published7 Aug 2025
- disclosed28 May 2025
- creditHiroki Kurosawa
Introduced: 28 May 2025
CVE-2025-4947 (opens in a new tab)How to fix?
Upgrade libcurl to version 8.15.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Certificate Validation when wolfSSL is used as the TLS backend for QUIC. An attacker can impersonate a legitimate server or perform a man-in-the-middle attack by exploiting a skipped certificate verification.
Note: The skip of the certificate verification for QUIC connections only occurs when connecting to a host specified as an IP address in the URL
PoC
1) Prepare curl with WolfSSL backend.
2) To resolve the domain name google.com and obtain its IP address for testing purposes(142.251.222.14).
3) curl --http3 https://142.251.222.14