Cyber Resilience

CVE-2024-21312

Microsoft .Net Framework 3.5 … 4.8.1

Published
09 January 2024
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.036 88th percentile
Risk Priority 64 floored blend · peak EPSS

Summary

CVE-2024-21312 is a high-severity Improper Input Validation (CWE-20) vulnerability in Microsoft .Net Framework. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 12% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2024-21312 is a denial-of-service vulnerability in the .NET Framework that carries a CVSS 3.1 base score of 7.5. The flaw is associated with CWE-20 and permits an unauthenticated network attacker to trigger a high-impact availability condition without any user interaction.

An attacker can send specially crafted requests over the network to affected .NET Framework installations, resulting in service disruption while leaving confidentiality and integrity unaffected. The attack requires no privileges and can be performed remotely with low complexity.

Microsoft has published remediation guidance for the issue through its Security Response Center, and NetApp has issued a corresponding advisory referencing the same CVE. The associated EPSS score has remained flat at 0.0588 with no material increase since disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

.NET Framework Denial of Service Vulnerability

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1036.001 Invalid Code Signature Stealth
Adversaries may attempt to mimic features of valid code signatures to increase the chance of deceiving a user, analyst, or tool.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-36873Same product: Microsoft .Net Framework
CVE-2023-36049Same product: Microsoft .Net Framework
CVE-2024-26253Same product: Microsoft Windows 10 1607
CVE-2024-30087Same product: Microsoft Windows 10 1607
CVE-2024-26240Same product: Microsoft Windows 10 1607
CVE-2024-26173Same product: Microsoft Windows 10 1607
CVE-2024-38055Same product: Microsoft Windows 10 1607
CVE-2024-38052Same product: Microsoft Windows 10 1607
CVE-2024-30078Same product: Microsoft Windows 10 1607
CVE-2024-26181Same product: Microsoft Windows 10 1607

Affected Assets

microsoft
.net framework
3.5, 4.6.2, 4.7, 4.7.1, 4.7.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing input validation through analysis or test cases.

SI-10 directly requires validity checks on information inputs, structurally preventing improper or missing validation.

Requiring documented development standards and tools can embed input-validation practices into the engineering process.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require and enforce input validation during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.

prevents

Secure-coding guidelines and mandatory security testing (including code scans) compel developers to validate and sanitize inputs at design and implementation time, lowering the incidence of malformed or malicious data reaching downstream components.

prevents

Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.

prevents

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

prevents

Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.

none

Regular automated validation of system software and data content, combined with scanning of all inbound files, enforces input validation at the boundary before untrusted content is processed.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

RHEL 8 (1 rule)
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-20

References