uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still using it for the handshake. Versions 1.6.0 through 1.8.0 contain a fingerprint mismatch with Chrome when using GREASE ECH, related to cipher suite selection. When Chrome selects the preferred cipher suite in the outer ClientHello and for ECH, it does so consistently based on hardware support—for example, if it prefers AES for the outer cipher suite, it also uses AES for ECH. However, the Chrome parrot in uTLS hardcodes AES preference for outer cipher suites but selects the ECH cipher suite randomly between AES and ChaCha20. This creates a 50% chance of selecting ChaCha20 for ECH while using AES for the outer cipher suite, a combination impossible in Chrome. This issue only affects GREASE ECH; in real ECH, Chrome selects the first valid cipher suite when AES is preferred, which uTLS handles correctly. This issue has been fixed in version 1.8.1.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still     using it for the handshake. Versions 1.6.0 through 1.8.0 contain a fingerprint mismatch with Chrome when     using GREASE ECH, related to cipher suite selection. When Chrome selects the preferred cipher suite in the     outer ClientHello and for ECH, it does so consistently based on hardware supportfor example, if it     prefers AES for the outer cipher suite, it also uses AES for ECH. However, the Chrome parrot in uTLS     hardcodes AES preference for outer cipher suites but selects the ECH cipher suite randomly between AES and     ChaCha20. This creates a 50% chance of selecting ChaCha20 for ECH while using AES for the outer cipher     suite, a combination impossible in Chrome. This issue only affects GREASE ECH; in real ECH, Chrome selects     the first valid cipher suite when AES is preferred, which uTLS handles correctly. This issue has been     fixed in version 1.8.1. (CVE-2026-27017)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still
    using it for the handshake. Versions 1.6.0 through 1.8.0 contain a fingerprint mismatch with Chrome when
    using GREASE ECH, related to cipher suite selection. When Chrome selects the preferred cipher suite in the
    outer ClientHello and for ECH, it does so consistently based on hardware support—for example, if it
    prefers AES for the outer cipher suite, it also uses AES for ECH. However, the Chrome parrot in uTLS
    hardcodes AES preference for outer cipher suites but selects the ECH cipher suite randomly between AES and
    ChaCha20. This creates a 50% chance of selecting ChaCha20 for ECH while using AES for the outer cipher
    suite, a combination impossible in Chrome. This issue only affects GREASE ECH; in real ECH, Chrome selects
    the first valid cipher suite when AES is preferred, which uTLS handles correctly. This issue has been
    fixed in version 1.8.1. (CVE-2026-27017)

ID	Name	Product	Family	Severity
299829	Linux Distros Unpatched Vulnerability : CVE-2026-27017	Nessus	Misc.	low
437849	SCA: security update for github.com/refraction-networking/utls (GHSA-7m29-f4hw-g2vx)	Tenable Cloud Security	SCA Checks	low
437849	SCA: security update for github.com/refraction-networking/utls (GHSA-7m29-f4hw-g2vx)	Tenable Self-Hosted Container Security	SCA Checks	low

Detections

Analytics

CVE-2026-27017

low

Tenable Plugins

low

low

low