CVE-2025-26646: External control of file name or path in .NET, Visual Studio, and Build Tools for Visual Studio allows an auth

This month

HIGH 8.0WATCHLISTUPGRADEUPGRADEUPGRADE

CVE-2025-26646 is a high-severity flaw (CVSS 8.0) affecting build tools, visual studio 2022, .net. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

External control of file name or path in .NET, Visual Studio, and Build Tools for Visual Studio allows an authorized attacker to perform spoofing over a network.

Why this priority

High severity
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	8.0 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	Required
EPSS exploit chance	1.3% (top 30%)
CISA exploited list	No
Weakness	CWE-73
Published	2025-05-13
Last modified	2026-06-17

Publisher (CNA): Microsoft Corporation · Vendor: microsoft

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-05-13 22:15 UTCPublished CVE record published
2026-06-17 09:02 UTCUpdated Record last modified

microsoft build tools UPGRADE

Affected: < 17.13.7

Fixed in: 17.13.7

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy build-tools || rpm -q build-tools || build-tools --version

2. UPGRADE to 17.13.7 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade build-tools

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade build-tools

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

microsoft visual studio 2022 UPGRADE

Affected: >= 17.8.0 and < 17.8.21 · >= 17.10.0 and < 17.10.15 · >= 17.12.0 and < 17.12.8 · >= 17.13.0 and < 17.13.7

Fixed in: 17.8.21, 17.10.15, 17.12.8, 17.13.7

Safe to downgrade to: a release before 17.8.0

1. Check installed version

apt-cache policy visual-studio-2022 || rpm -q visual-studio-2022 || visual-studio-2022 --version

2. UPGRADE to 17.8.21 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade visual-studio-2022

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade visual-studio-2022

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 17.8.0 (Debian / Ubuntu)

apt-cache madison visual-studio-2022 sudo apt install visual-studio-2022=<VERSION_BEFORE_17.8.0> sudo apt-mark hold visual-studio-2022

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list visual-studio-2022 sudo dnf downgrade visual-studio-2022-<VERSION_BEFORE_17.8.0> sudo dnf versionlock add visual-studio-2022

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

microsoft .net UPGRADE

Affected: >= 9.0.0 and < 9.0.5 · >= 8.0.0 and < 8.0.16

Fixed in: 8.0.16, 9.0.5

Safe to downgrade to: a release before 8.0.0

1. Check installed version

apt-cache policy .net || rpm -q .net || .net --version

2. UPGRADE to 8.0.16 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade .net

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade .net

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 8.0.0 (Debian / Ubuntu)

apt-cache madison .net sudo apt install .net=<VERSION_BEFORE_8.0.0> sudo apt-mark hold .net

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list .net sudo dnf downgrade .net-<VERSION_BEFORE_8.0.0> sudo dnf versionlock add .net

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-26646?

build tools: upgrade to 17.13.7; visual studio 2022: upgrade to 17.8.21, 17.10.15, 17.12.8, 17.13.7; .net: upgrade to 8.0.16, 9.0.5. Exact commands for each OS are on this page.

Is CVE-2025-26646 being exploited?

CVE-2025-26646 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-26646 affect?

CVE-2025-26646 affects build tools, visual studio 2022, .net. Severity is high (CVSS 8.0). External control of file name or path in .NET, Visual Studio, and Build Tools for Visual Studio allows an authorized attacker to perform spoofing over a network.

How urgent is CVE-2025-26646?

Priority 50/100. High severity; On your watchlist

Software pages

Visual Studio vulnerabilities

References

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