Microsoft .NET Core and Visual Studio Denial-of-Service
CVE-2023-38180 is a high-severity uncontrolled resource consumption vulnerability in .NET 6.0 from Microsoft, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 6.0.21 as the first without the flaw, so updating .NET 6.0 to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on August 9, 2023, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update .NET 6.0 to 6.0.21 or a later version.
- Update .NET 7.0 to 7.0.10 or a later version.
- Update ASP.NET Core 2.1 to 2.1.40 or a later version.
- CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | .NET 6.0 | 6.0.0 up to, but not including, 6.0.21 | 6.0.21 |
| Microsoft | .NET 7.0 | 7.0.0 up to, but not including, 7.0.10 | 7.0.10 |
| Microsoft | ASP.NET Core 2.1 | 2.0 up to, but not including, 2.1.40 | 2.1.40 |
| Microsoft | Microsoft Visual Studio 2022 version 17.2 | 17.2.0 up to, but not including, 17.2.18 | 17.2.18 |
| Microsoft | Microsoft Visual Studio 2022 version 17.4 | 17.4.0 up to, but not including, 17.4.10 | 17.4.10 |
| Microsoft | Microsoft Visual Studio 2022 version 17.6 | 17.6.0 up to, but not including, 17.6.6 | 17.6.6 |
| Microsoft | .net | 6.0.0 up to, but not including, 6.0.21; 7.0.0 up to, but not including, 7.0.10 | 6.0.21, 7.0.10 |
| Microsoft | Asp.net Core | 2.1 up to, but not including, 2.1.40 | 2.1.40 |
| Microsoft | Visual Studio 2022 | 17.2.0 up to, but not including, 17.2.18; 17.4.0 up to, but not including, 17.4.10; 17.6.0 up to, but not including, 17.6.6 | 17.2.18, 17.4.10, 17.6.6 |
| Fedora Project | Fedora | 37; 38 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (microsoft.com).
Official description
.NET and Visual Studio Denial of Service Vulnerability
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How developers prevent this class of flaw
- Ensure that protocols have specific limits of scale placed on them.
- Ensure that all failures in resource allocation place the system into a safe posture.
More Uncontrolled Resource Consumption vulnerabilities (CWE-400)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-38180US Government Resource
Other references
Other vulnerabilities in .NET 6.0
- 8.8 High severity
- 8.1 High severity
- 7.5 High severity
Recent Uncontrolled Resource Consumption vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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