Use of a Cryptographic Primitive with a Risky Implementation Affecting github.com/refraction-networking/utls package, versions >=1.6.0 <1.8.1
Threat Intelligence
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-GOLANG-GITHUBCOMREFRACTIONNETWORKINGUTLS-15317314
- published19 Feb 2026
- disclosed18 Feb 2026
- creditacgdaily
Introduced: 18 Feb 2026
CVE-2026-27017 (opens in a new tab)How to fix?
Upgrade github.com/refraction-networking/utls to version 1.8.1 or higher.
Overview
Affected versions of this package are vulnerable to Use of a Cryptographic Primitive with a Risky Implementation in the HelloChrome_120, HelloChrome_120_PQ, HelloChrome_131 and HelloChrome_133 symbols due to inconsistent ciphersuite selection between the outer ClientHello and ECH for GREASE ECH. An attacker can distinguish clients by analyzing the fingerprint mismatch between the outer and ECH ciphersuites, potentially allowing client identification through passive network observation.