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CVE Record

CVE-2026-32203: .NET and Visual Studio Denial of Service Vulnerability

Stack-based buffer overflow in .NET and Visual Studio allows an unauthorized attacker to deny service over a network.

HighCVSS 7.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2026-32203 is a high-severity denial-of-service issue in Microsoft .NET and Visual Studio. A network attacker without authentication may be able to crash affected software. The business risk is service disruption, not confirmed data theft or code execution based on the provided sources.

Executive priority

Treat this as a high-priority availability risk. Patch exposed production .NET environments and developer systems promptly, with highest urgency for public-facing services or systems supporting critical operations.

Technical view

The sources describe a stack-based buffer overflow with input validation and out-of-bounds write weakness mappings. Affected entries include .NET 8.0.0, 9.0.0, 10.0.0, and specified Visual Studio 2022/2026 versions. CVSS 7.5 reflects network reachability, low complexity, no privileges, no user interaction, and high availability impact.

Likely exposure

Exposure is most likely where affected .NET runtimes, SDKs, or Visual Studio versions are installed, especially supporting network-reachable .NET applications. Red Hat references indicate downstream advisories exist, but the provided bundle does not specify affected Red Hat package names.

Exploitation context

The bundle does not show known active exploitation: KEV is false and CVSS exploit maturity is unproven. The vulnerability is still operationally important because the attack vector is network-based and requires no authentication or user interaction.

Researcher notes

Evidence is limited to advisory metadata. The source bundle names weakness classes and affected versions but does not include root-cause detail, proof of concept, or fixed version numbers. Avoid assuming remote code execution; the stated impact is denial of service.

Mitigation direction

  • Apply Microsoft updates from the MSRC advisory for affected .NET and Visual Studio versions.
  • Review Red Hat advisories if consuming .NET packages through Red Hat channels.
  • Prioritize internet-facing or business-critical .NET services first.
  • Use vendor guidance for exact fixed versions and deployment requirements.
  • Apply normal change controls for runtime and developer tool updates.

Validation and detection

  • Inventory installed .NET 8.0.0, 9.0.0, 10.0.0 runtimes and SDKs.
  • Check Visual Studio installations for listed affected 17.12, 17.14, and 18.4 versions.
  • Map affected runtimes to exposed .NET applications and service owners.
  • Confirm vendor patches are installed through package manager or product update records.
  • Monitor service availability after patching for crash or restart patterns.
Prepared
Confidence
medium
Sources
8

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-121: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · low confidence lookup

CWE-20: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · low confidence lookup

CWE-787: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-32203 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
22Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: yesTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C3.93.6microsoft
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6redhat-SADP

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-32203Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Reported to Red Hat.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Made public.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPdotnet: .NET: Denial of Service via stack overflow
other:Red Hat severity ratingcvssV3_1
  • 2026-04-13T05:02:08.475Z: Reported to Red Hat.
  • 2026-04-14T18:39:07.491Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Microsoft.NET 10.010.0.0Listed
Microsoft.NET 8.08.0.0Listed
Microsoft.NET 9.09.0.0Listed
MicrosoftMicrosoft Visual Studio 2022 version 17.1217.12.0Listed
MicrosoftMicrosoft Visual Studio 2022 version 17.1417.14.0Listed
MicrosoftMicrosoft Visual Studio 2026 version 18.418.4.0Listed
Weakness

CWE details

CWE-121CWE-20CWE-787

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-121 · source CWE mapping

Stack-based Buffer Overflow

Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
CWE-20 · source CWE mapping

Improper Input Validation

Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
CWE-787 · source CWE mapping

Out-of-bounds Write

Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs