Deserialization of Untrusted Data in Microsoft Exchange Server - CVE-2023-36039

Vulnerability identifier: #VU83066

CSH Severity: Medium

CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2023-36039

CWE-ID: CWE-502

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote user to gain access to sensitive information.

The vulnerability exists due to an error within the SerializationTypeConverter class in FederationTrust. A remote user on the local network can access a user's Net-NTLMv2 hash and perform NTLM Relay attack against another service to authenticate as the user.

Microsoft Exchange Server

Install updates from vendor's website.

Microsoft Exchange Server - addressed in versions 2016 CU23 Nov23SU 15.01.2507.035, 2019 CU12 Nov23SU 15.02.1118.040, 2019 CU13 Nov23SU 15.02.1258.028

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2023-36039
• https://www.zerodayinitiative.com/advisories/ZDI-23-1641/

• Multiple vulnerabilities in Microsoft Exchange Server