# CVE-2026-118147 — Microsoft Visual Studio 2017 version 15.9

> As of 2026-11-06, CVE-2026-118147 is a HIGH-severity vulnerability in Microsoft Visual Studio 2017 version 15.9, CVSS v3.1 7.4, EPSS 0.6% (49.3th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-118147, most recently “Multiple Vulnerabilities in Microsoft Edge (Chromium) and Visual Studio 2017-2026 - HK GovCERT Alert A26-11-02 (CVE-2026-91732, CVE-2026-118147, CVE-2026-118322)”.

**Last updated:** 2026-10-31

## What is CVE-2026-118147?

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

The record classifies CVE-2026-118147 under weakness class [CWE-295](https://intel.threadlinqs.com/cwe/CWE-295). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity. 4 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 7 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.4 — HIGH (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C`)
- **EPSS (FIRST):** 0.6% probability of exploitation in the next 30 days, higher than 49.3% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-10-31

## Is CVE-2026-118147 being exploited?

It currently carries a trending score of 47 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Microsoft](https://intel.threadlinqs.com/vendors/microsoft): Visual Studio 2017 version 15.9, Visual Studio 2019 version 16.11, Visual Studio 2022 version 17.14, Visual Studio 2026 version 18.11

## How to fix CVE-2026-118147

Patch reference: [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118147](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118147). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-118147

1 tracked threat in the Threadlinqs corpus references CVE-2026-118147, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple Vulnerabilities in Microsoft Edge (Chromium) and Visual Studio 2017-2026 - HK GovCERT Alert A26-11-02 (CVE-2026-91732, CVE-2026-118147, CVE-2026-118322)](https://intel.threadlinqs.com/threat/TL-2026-5450) — HIGH · 2026-11-06

## Sources

Enriched from CVE.org, NVD, GitHub Security Advisories, FIRST EPSS. Last verified by Threadlinqs on 2026-11-02. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [msrc.microsoft.com — vendor advisory](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118147)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-118147
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