How severe is CVE-2023-36049?

CVE-2023-36049 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-36049?

CVE-2023-36049 affects the following packages: System.Net.Requests (NuGet), System.Net.Requests (NuGet), System.Net.Requests (NuGet). Ecosystems affected: NuGet.

How do I fix CVE-2023-36049?

Update System.Net.Requests to 8.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-36049 is resolved across your whole dependency graph.

How do I detect CVE-2023-36049 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for System.Net.Requests, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2023-36049 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2023-36049?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-36049 can be triaged on real exposure rather than presence alone.

Is CVE-2023-36049 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-36049 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-36049?

CVE-2023-36049 has an EPSS (Exploit Prediction Scoring System) score of 12.5%, placing it in the 96th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score warrants monitoring and prompt remediation.

What type of vulnerability is CVE-2023-36049?

CVE-2023-36049 is classified as Improper Input Validation (CWE-20). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2023-36049 published, and has it been updated?

CVE-2023-36049 was published on November 14, 2023 and was last updated on July 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET

.NET NuGet

Not in CISA KEV

CRITICAL severity

CVE-2023-36049 — System.Net.Requests

CRITICAL

CVE-2023-36049 is a critical-severity (CVSS 9.8) Improper Input Validation vulnerability in System.Net.Requests. EPSS puts its 30-day exploitation probability at 12.5% (96th percentile). A fix is available for System.Net.Requests — see the affected versions and patch details below.

Microsoft Security Advisory CVE-2023-36049: .NET Elevation of Privilege Vulnerability

Also known asBIT-dotnet-2023-36049BIT-dotnet-sdk-2023-36049GHSA-c3hf-8vgx-72rh

Published

Nov 14, 2023

Updated

Jul 8, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

Exploitation data as of Sep 22, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

12.5%probability of exploitation in next 30 days

Moderate Risk0.00%

Lower risk than most CVEs96th percentile — riskier than 96% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2023-36049 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 378,156 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

3 pkgs affected

.NETSystem.Net.Requests.NETSystem.Net.Requests.NETSystem.Net.Requests

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

Microsoft Security Advisory CVE-2023-36049: .NET Elevation of Privilege Vulnerability

<a name="executive-summary"></a>Executive summary

Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 6.0, .NET 7.0 and .NET 8.0 RC2. This advisory also provides guidance on what developers can do to update their applications to address this vulnerability.

An elevation of privilege vulnerability exists in .NET where untrusted URIs provided to System.Net.WebRequest.Create can be used to inject arbitrary commands to backend FTP servers.

Announcement

Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/287

<a name="mitigation-factors"></a>Mitigation factors

Microsoft has not identified any mitigating factors for this vulnerability.

<a name="affected-software"></a>Affected software

Any .NET 6.0 application running on .NET 6.0.24 or earlier.
Any .NET 7.0 application running on .NET 7.0.13 or earlier.
Any .NET 8.0 application running on .NET 8.0 RC2.

Advisory FAQ

<a name="how-affected"></a>How do I know if I am affected?

If you have a runtime or SDK with a version listed, or an affected package listed in affected software, you're exposed to the vulnerability.

<a name="how-fix"></a>How do I fix the issue?

To fix the issue please install the latest version of .NET 8.0 or .NET 7.0 or .NET 6.0. If you have installed one or more .NET SDKs through Visual Studio, Visual Studio will prompt you to update Visual Studio, which will also update your .NET SDKs.
If you are using one of the affected packages, please update to the patched version listed above.
If you have .NET 6.0 or greater installed, you can list the versions you have installed by running the dotnet --info command. You will see output like the following;

.NET Core SDK (reflecting any global.json):

 Version:   6.0.200
 Commit:    8473146e7d

Runtime Environment:

 OS Name:     Windows
 OS Version:  10.0.18363
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.300\

Host (useful for support):

  Version: 6.0.5
  Commit:  8473146e7d

.NET Core SDKs installed:

  6.0.200 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:

  Microsoft.AspNetCore.App 6.0.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 6.0.5 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download

If you're using .NET 8.0, you should download and install .NET 8.0.0 Runtime or .NET 8.0.100 SDK (for Visual Studio 2022 v17.8) from https://dotnet.microsoft.com/download/dotnet-core/8.0.
If you're using .NET 7.0, you should download and install Runtime 7.0.14 or SDK 7.0.114 (for Visual Studio 2022 v17.4) from https://dotnet.microsoft.com/download/dotnet-core/7.0.
If you're using .NET 6.0, you should download and install Runtime 6.0.25 or SDK 6.0.317 (for Visual Studio 2022 v17.2) from https://dotnet.microsoft.com/download/dotnet-core/6.0.

.NET 6.0 and .NET 7.0 updates are also available from Microsoft Update. To access this either type "Check for updates" in your Windows search, or open Settings, choose Update & Security and then click Check for Updates.

Once you have installed the updated runtime or SDK, restart your apps for the update to take effect.

Additionally, if you've deployed self-contained applications targeting any of the impacted versions, these applications are also vulnerable and must be recompiled and redeployed.

Other Information

Reporting Security Issues

If you have found a potential security issue in .NET 8.0 or .NET 7.0 or .NET 6.0, please email details to [email protected]. Reports may qualify for the Microsoft .NET Core & .NET 5 Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at https://aka.ms/corebounty.

Support

You can ask questions about this issue on GitHub in the .NET GitHub organization. The main repos are located at https://github.com/dotnet/runtime and https://github.com/dotnet/aspnet/. The Announcements repo (https://github.com/dotnet/Announcements) will contain this bulletin as an issue and will include a link to a discussion issue. You can ask questions in the linked discussion issue.

Disclaimer

The information provided in this advisory is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

External Links

CVE-2023-36049

Revisions

V1.0 (November 14, 2023): Advisory published.

Version 1.0

Last Updated 2023-11-14

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`System.Net.Requests`	≥ 8.0.0-rc.2.23480.2&&< 8.0.0	8.0.0`dotnet add package System.Net.Requests --version 8.0.0`
.NETNuGet	`System.Net.Requests`	≥ 6.0.0&&< 6.0.25	6.0.25`dotnet add package System.Net.Requests --version 6.0.25`
.NETNuGet	`System.Net.Requests`	≥ 7.0.0&&< 7.0.14	7.0.14`dotnet add package System.Net.Requests --version 7.0.14`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for System.Net.Requests, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update System.Net.Requests to 8.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-36049 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-36049 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2023-36049. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

The vulnerability identified in FormatFtpCommand within the .NET package presents a moderate severity concern rather than an important one due to several mitigating factors. Firstly, while it allows for CRLF (Carriage Return Line Feed) injection, enabling potential arbitrary file write and deletion, its impact is…

Product	Fixed in	Advisory
.NET Core on Red Hat Enterprise Linux	`rh-dotnet60-dotnet-0:6.0.125-1.el7_9`	RHSA-2023:7259
Red Hat Enterprise Linux 8	`dotnet8.0-0:8.0.100-2.el8_9`	RHSA-2023:7254
Red Hat Enterprise Linux 8	`dotnet7.0-0:7.0.114-1.el8_9`	RHSA-2023:7256
Red Hat Enterprise Linux 8	`dotnet6.0-0:6.0.125-1.el8_9`	RHSA-2023:7258
Red Hat Enterprise Linux 9	`dotnet8.0-0:8.0.100-2.el9_3`	RHSA-2023:7253
Red Hat Enterprise Linux 9	`dotnet7.0-0:7.0.114-1.el9_3`	RHSA-2023:7255
Red Hat Enterprise Linux 9	`dotnet6.0-0:6.0.125-1.el9_3`	RHSA-2023:7257

UbuntuCRITICAL

USN-6480-1Ubuntu

Frequently Asked Questions

# Microsoft Security Advisory CVE-2023-36049: .NET Elevation of Privilege Vulnerability ## <a name="executive-summary"></a>Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 6.0, .NET 7.0 and .NET 8.0 RC2. This advisory also provides guidance on what developers can do to update their applications to address this vulnerability. An elevation of privilege vulnerability exists in .NET where untrusted URIs provided to System.Net.WebRequest.Create can be used to inject arbitrary commands to backend FTP servers. ## Announcement A

O3 Security · Impact-Aware SCA

Is CVE-2023-36049 in your dependencies?

O3 Security finds CVE-2023-36049 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works

CVSS Score

9.8/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE Classification

CWE-20Improper Input Validation

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

runtime

6.5/10

Code-Review10/10

Maintained10/10

Branch-Protection8/10

Assessed Sep 21, 2026

Timeline

Disclosed

Nov 14, 2023

Last updated

Jul 8, 2026

Identifiers

CVE-2023-36049

GHSA-c3hf-8vgx-72rh

BIT-dotnet-2023-36049

BIT-dotnet-sdk-2023-36049

References

Advisorynvd.nist.gov Fixmsrc.microsoft.com Webgithub.com Webgithub.com Packagegithub.com

Related vulnerabilities

This CVE is critical severity — higher than any of the other 8 CVEs with CWE-20 (highest there: high).

CVE-2026-61794CVE-2026-81875CVE-2026-81876CVE-2026-61793GHSA-2xmm-m4wv-3fjhCVE-2026-56831CVE-2026-54529GHSA-cc9r-2j5m-2m83Browse all CWE-20

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedJul 8, 2026

CVE-2023-36049 — System.Net.Requests

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Microsoft Security Advisory CVE-2023-36049: .NET Elevation of Privilege Vulnerability

<a name="executive-summary"></a>Executive summary

Announcement

<a name="mitigation-factors"></a>Mitigation factors

<a name="affected-software"></a>Affected software

Advisory FAQ

<a name="how-affected"></a>How do I know if I am affected?

<a name="how-fix"></a>How do I fix the issue?

Other Information

Reporting Security Issues

Support

Disclaimer

External Links

Revisions

Affected Packages

Detection & mitigation playbook

Detect

Fix

Workarounds

How O3 protects you

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2023-36049 in your dependencies?