PatchTheCVECVE-2026-50649: Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code locally.
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HIGH 7.8WATCHLISTDOWNGRADEUPGRADEUPGRADE
CVE-2026-50649 is a high-severity flaw (CVSS 7.8) affecting .net framework, .net, visual studio 2026. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code locally.
Why this priority
- High severity
- EPSS top 10%: very likely to be exploited
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.8 (High) |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 4.0% (top 10%) |
| CISA exploited list | No |
| Weakness | CWE-502 |
| Published | 2026-07-14 |
| Last modified | 2026-07-24 |
Publisher (CNA): Microsoft Corporation · Vendor: microsoft
Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
microsoft .net framework DOWNGRADE
Affected: 4.8.1 · 4.8 · 4.6.2 · 4.7 · 4.7.1 · 4.7.2 · 3.5
Fixed in: no fixed release known
Safe to downgrade to: a release before 3.5
1. Check installed version
apt-cache policy .net-framework || rpm -q .net-framework || .net-framework --version
2. No fixed release: DOWNGRADE to a release before 3.5 (Debian / Ubuntu)
apt-cache madison .net-framework
sudo apt install .net-framework=<VERSION_BEFORE_3.5>
sudo apt-mark hold .net-framework
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list .net-framework
sudo dnf downgrade .net-framework-<VERSION_BEFORE_3.5>
sudo dnf versionlock add .net-framework
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: >= 8.0.0 and < 8.0.29 · >= 9.0.0 and < 9.0.18
Fixed in: 8.0.29, 9.0.18
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 8.0.29 (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.
microsoft visual studio 2026 UPGRADE
Affected: >= 18.7.0 and < 18.7.4
Fixed in: 18.7.4
Safe to downgrade to: a release before 18.7.0
1. Check installed version
apt-cache policy visual-studio-2026 || rpm -q visual-studio-2026 || visual-studio-2026 --version
2. UPGRADE to 18.7.4 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade visual-studio-2026
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade visual-studio-2026
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 18.7.0 (Debian / Ubuntu)
apt-cache madison visual-studio-2026
sudo apt install visual-studio-2026=<VERSION_BEFORE_18.7.0>
sudo apt-mark hold visual-studio-2026
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list visual-studio-2026
sudo dnf downgrade visual-studio-2026-<VERSION_BEFORE_18.7.0>
sudo dnf versionlock add visual-studio-2026
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.
Exact fixes by distribution
A distro patch exists: prefer upgrading over downgrading.
Fedora ELN · gram_grep · FIXED · 0.10.3-2.eln159 · FEDORA-2026-29427819d0 · source
sudo dnf upgrade --advisory=FEDORA-2026-29427819d0
Fedora 46 · python3.11 · FIXED · 3.11.18-1.fc46 · FEDORA-2026-cc775894f4 · source
sudo dnf upgrade --advisory=FEDORA-2026-cc775894f4
Ubuntu 22.04 · dotnet6 · NOT AFFECTED
Ubuntu 22.04 · dotnet8 · NOT AFFECTED
Ubuntu 24.04 · dotnet8 · NOT AFFECTED
Ubuntu 24.04 · dotnet10 · NOT AFFECTED
RHEL 10 · dotnet8.0 · FIXED · dotnet8.0-8.0.129-1.el10_2
sudo dnf upgrade --advisory=RHSA-2026:41893
rpm -q dotnet8.0
RHEL 10 · dotnet9.0 · FIXED · dotnet9.0-9.0.119-1.el10_2
sudo dnf upgrade --advisory=RHSA-2026:41895
rpm -q dotnet9.0
RHEL 10 · dotnet10.0 · FIXED · dotnet10.0-10.0.110-1.el10_2
sudo dnf upgrade --advisory=RHSA-2026:41897
rpm -q dotnet10.0
RHEL 10.0 Extended Update Support · dotnet8.0 · FIXED · dotnet8.0-8.0.130-1.el10_0
sudo dnf upgrade --advisory=RHSA-2026:58566
rpm -q dotnet8.0
RHEL 10.0 Extended Update Support · dotnet9.0 · FIXED · dotnet9.0-9.0.120-1.el10_0
sudo dnf upgrade --advisory=RHSA-2026:58567
rpm -q dotnet9.0
Alpine 3.22 · dotnet8-runtime · FIXED · dotnet8-runtime-8.0.29-r0
apk add --upgrade dotnet8-runtime
apk info -v dotnet8-runtime
Alpine 3.22 · dotnet9-runtime · FIXED · dotnet9-runtime-9.0.18-r0
apk add --upgrade dotnet9-runtime
apk info -v dotnet9-runtime
Alpine 3.23 · dotnet10-runtime · FIXED · dotnet10-runtime-10.0.10-r0
apk add --upgrade dotnet10-runtime
apk info -v dotnet10-runtime
Alpine 3.23 · dotnet8-runtime · FIXED · dotnet8-runtime-8.0.29-r0
apk add --upgrade dotnet8-runtime
apk info -v dotnet8-runtime
sudo dnf update --advisory=ALAS2023-2026-2048
Install KB5104032 via Windows Update, then verify:
Get-HotFix -Id KB5104032
Install KB5104033 via Windows Update, then verify:
Get-HotFix -Id KB5104033
Microsoft .NET Framework 3.5 on Windows 11 version 26H1 for x64-based Systems · KB5101014 · FIXED · 2.0.50727.9182 & 3.0.30729.9168 · KB5101014 · source
Install KB5101014 via Windows Update, then verify:
Get-HotFix -Id KB5101014
Microsoft .NET Framework 3.5 on Windows 11 Version 26H1 for ARM64-based Systems · KB5101014 · FIXED · 2.0.50727.9182 & 3.0.30729.9168 · KB5101014 · source
Install KB5101014 via Windows Update, then verify:
Get-HotFix -Id KB5101014
Microsoft .NET Framework 4.8.1 on Windows 11 version 26H1 for x64-based Systems · KB5101002 · FIXED · 4.8.9340.0 · KB5101002 · source
Install KB5101002 via Windows Update, then verify:
Get-HotFix -Id KB5101002
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.
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-2026-50649?
.net framework: downgrade or apply the listed mitigation; .net: upgrade to 8.0.29, 9.0.18; visual studio 2026: upgrade to 18.7.4. Exact commands for each OS are on this page.
Is CVE-2026-50649 being exploited?
CVE-2026-50649 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-2026-50649 affect?
CVE-2026-50649 affects .net framework, .net, visual studio 2026. Severity is high (CVSS 7.8). Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code locally.
How urgent is CVE-2026-50649?
Priority 55/100. High severity; EPSS top 10%: very likely to be exploited; On your watchlist
Software pages
.NET vulnerabilities · Visual Studio vulnerabilities
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