SB2026071737 - Multiple vulnerabilities in Microsoft .NET Framework

Description

This security bulletin contains information about 2 vulnerabilities.

1) Deserialization of Untrusted Data (CVE-ID: CVE-2026-50652)

CWE-ID: CWE-502 - Deserialization of Untrusted Data

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to deserialization of untrusted data in Azure Active Directory when processing untrusted serialized data over the network. A remote attacker can send crafted serialized data to cause a denial of service.

2) Infinite loop (CVE-ID: CVE-2026-50653)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to loop with unreachable exit condition ('infinite loop') in Azure Active Directory when handling network requests. A remote attacker can send crafted requests to cause a denial of service.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-50652
• https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/releases/tag/8.19.2
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-50653