Cyber Resilience

CVE-2026-50528

Access Control in Microsoft .Net 8.0.0 – 8.0.29

Access Control
Published
14 July 2026
Modified
22 July 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
EPSS Score 0.0055 43th percentile
Risk Priority 62 floored blend · peak EPSS

Summary

CVE-2026-50528 is a high-severity Authentication Bypass by Assumed-Immutable Data (CWE-302) vulnerability in Microsoft .Net. Its CVSS base score is 8.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-25 (Reference Monitor) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access ControlA07:2025 Authentication FailuresA10:2025 Mishandling of Exceptional Conditions

EU & UK References

Vulnerability Data

Incorrect authorization in .NET allows an unauthorized attacker to bypass a security feature over a network.

CWE(s)
CWE-302CWE-636CWE-863

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
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.
attack.mitre.org →
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
attack.mitre.org →
T1548.002 Bypass User Account Control Privilege Escalation
Adversaries may bypass UAC mechanisms to elevate process privileges on system.
attack.mitre.org →
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
attack.mitre.org →
T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-47303Same product: Apple Macos
CVE-2026-6406Same product: Apple Macos
CVE-2026-12446Same product: Apple Macos
CVE-2026-28726Same product: Linux Linux Kernel
CVE-2023-2257Same product: Apple Macos
CVE-2026-48303Same product: Linux Linux Kernel
CVE-2026-48333Same product: Linux Linux Kernel
CVE-2026-48348Same product: Apple Macos
CVE-2026-21274Same product: Apple Macos
CVE-2026-28720Same product: Linux Linux Kernel

Affected Assets

microsoft
.net
8.0.0 — 8.0.29 · 9.0.0 — 9.0.18 · 10.0.0 — 10.0.6
microsoft
visual studio 2022
17.12.0 — 17.12.22 · 17.14.0 — 17.14.36
microsoft
visual studio 2026
18.7.0 — 18.7.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V3.2.1
  • V7.4.1
  • V8.3.3
  • V10.3.4

Mitigating Controls (NIST 800-53 r5) AI

AC-3 Access Enforcement good match

AC-3 directly requires correct enforcement of authorization decisions on every access request, structurally preventing incorrect checks.

SC-24 Fail in Known State good match

SC-24 directly requires the system to fail to a known state that preserves security properties, structurally stopping fallback to a less-secure mode.

SI-17 Fail-safe Procedures good match

SI-17 mandates explicit fail-safe procedures that activate on indicated failures, preventing the insecure fallback behavior.

AC-24 Access Control Decisions good match

AC-24 ensures access-control decisions are made and applied consistently, reducing the chance of an incorrect authorization result.

AC-25 Reference Monitor good match

A reference monitor that is always invoked and tamper-proof forces every authorization decision through a verified, correct path.

CP-12 Safe Mode good match

CP-12 forces entry into a safe mode on detected conditions, limiting exposure but not covering every failure path.

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.AA-03 mostly match
prevents

Strong authentication mechanisms directly avoid reliance on attacker-controlled immutable data.

PR.AA-04 mostly match
prevents

Protecting and verifying identity assertions prevents tampering with data assumed immutable during auth.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

PR.PS-06 mostly match
prevents

Secure-development practices explicitly include designing error and failure handling to remain in a secure state.

PR.PS-01 partial match
prevents

Hardened baselines and configuration management reduce the chance that error paths default to insecure settings.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can discover and block authentication bypasses that rely on mutable data.

A.5.15 Access control partial match
degrades

Access-control policy can mandate validation of all identity data, reducing reliance on assumed-immutable fields.

A.5.16 Identity management partial match
degrades

Identity-management processes can require verification of mutable attributes, mitigating the root cause.

A.5.17 Authentication information partial match
degrades

Proper management of authentication information prevents use of client-controlled tokens or cookies as sole proof of identity.

A.5.18 Access rights partial match
mitigates

Access-rights reviews can detect and revoke rights granted via tampered immutable data.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC practices include threat modeling and input-validation requirements that catch assumed-immutable data flaws.

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).

Oracle Linux 8 (2 rules)
  • V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-863
  • V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863
RHEL 7 (1 rule)
  • V-204430 The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. prevents CWE-863
RHEL 8 (1 rule)
  • V-251712 The RHEL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863

References