Golang < 1.26.10 / 1.27.x < 1.27.3 Improper Certificate Validation

medium Nessus Plugin ID 371140

Synopsis

An application installed on the remote host is affected by an improper certificate validation vulnerability.

Description

The version of Golang running on the remote host is prior to 1.26.10, or 1.27.x prior to 1.27.3. It is, therefore, affected by an improper certificate validation vulnerability in the crypto/x509 package.

On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in crypto/x509 to return an error when calling Verify with any of the known intermediate certificates that are no longer considered to be trustworthy. (CVE-2026-111943)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Golang Go version 1.26.10, 1.27.3 or later.

See Also

https://go.dev/doc/devel/release#go1.27.3

https://go.dev/issue/82345

https://groups.google.com/g/golang-announce/c/66pojueaQek

https://pkg.go.dev/vuln/GO-2026-6809

https://www.openwall.com/lists/oss-security/2026/10/20/29

Plugin Details

Severity: Medium

ID: 371140

File Name: golang_1_26_10_1_27_3.nasl

Version: 1.2

Type: Local

Agent: windows, macosx, unix

Family: Misc.

Published: 10/23/2026

Updated: 10/23/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.1

Percentile: 98.15

CVSS v2

Risk Factor: High

Base Score: 7.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:N

CVSS Score Source: CVE-2026-111943

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

Vulnerability Information

CPE: cpe:/a:golang:go

Required KB Items: installed_sw/Golang Go Programming Language

Patch Publication Date: 10/20/2026

Vulnerability Publication Date: 10/20/2026

Reference Information

CVE: CVE-2026-111943

IAVB: 2026-B-0304