---
id: "CVE-2026-118147"
kind: "vulnerability"
aliases: ["CVE-2026-118147"]
title: "Visual Studio: improper certificate validation lets attackers spoof network connections"
severity: "high"
cvss: 7.4
epss: null
exploited: false
status: "open"
category: "other"
products: [{"name": "Visual Studio 2017 15.9", "fixed": ["15.9.84"], "affected": "< 15.9.84", "ecosystem": "vendor"}, {"name": "Visual Studio 2019 16.11", "fixed": ["16.11.62"], "affected": "< 16.11.62", "ecosystem": "vendor"}, {"name": "Visual Studio 2022 17.14", "fixed": ["17.14.44"], "affected": "< 17.14.44", "ecosystem": "vendor"}, {"name": "Visual Studio 2026 18.11", "fixed": ["18.11.3"], "affected": "< 18.11.3", "ecosystem": "vendor"}]
ecosystems: []
tags: ["mitm", "other", "spoofing", "visual-studio", "windows"]
not_affected_if: []
published_at: "2026-10-31T19:16:47+00:00"
first_seen_at: "2026-10-31T19:27:36+00:00"
updated_at: "2026-10-31T19:29:32+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118147", "first_seen_at": "2026-10-31T19:27:36+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-31T19:29:32+00:00"}]
---

# Visual Studio: improper certificate validation lets attackers spoof network connections

Visual Studio does not properly validate certificates (CWE-295). An attacker who can sit in the network path (machine-in-the-middle, high complexity) can impersonate a trusted server and read or alter the traffic. Microsoft fixed it on Oct 30, 2026 in all four supported branches.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Visual Studio 2017 15.9 affected < 15.9.84 fixed 15.9.84
- vendor:Visual Studio 2019 16.11 affected < 16.11.62 fixed 16.11.62
- vendor:Visual Studio 2022 17.14 affected < 17.14.44 fixed 17.14.44
- vendor:Visual Studio 2026 18.11 affected < 18.11.3 fixed 18.11.3

## How to check

Open Help > About Microsoft Visual Studio (or the Visual Studio Installer) and compare your build to the fixed build for your branch: 2017 15.9.84, 2019 16.11.62, 2022 17.14.44, 2026 18.11.3. Anything lower is affected.

## Fix

Update Visual Studio (not Windows) to at least 15.9.84, 16.11.62, 17.14.44 or 18.11.3 via the Visual Studio Installer.

## Timeline

- 2026-10-31T19:27:36+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-118147
- 2026-10-31T19:29:32+00:00 analyst — Read MSRC advisory: Important, CVSS 7.4, not exploited/not disclosed, 'Exploitation Less Likely'. Fixed builds 15.9.84 (VS2017; number from secondary listing, MSRC page build cell not shown), 16.11.62, 17.14.44, 18.11.3 (18.11.3 also on Learn release notes). A secondary site claims this is about eMudhra certificates; the MSRC page does not say so, so left out.

## Documents

- [advisory] MSRC: CVE-2026-118147 Visual Studio Spoofing Vulnerability https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118147
- [fix] Visual Studio 2026 release notes (18.11.3) https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes

## From the sources

Improper certificate validation in Visual Studio allows an unauthorized attacker to perform spoofing over a network.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_