#VU82692 Deserialization of Untrusted Data in Microsoft Exchange Server

Vulnerability identifier: #VU82692

Vulnerability risk: High

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: N/A

CWE-ID: CWE-502

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft Exchange Server
Server applications / Mail servers

Vendor: Microsoft

Description

The vulnerability allows a remote user to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data within the ChainedSerializationBinder class. A remote user can send specially crafted HTTP request to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Microsoft Exchange Server: 2016 Cumulative Update 1 15.01.0396.030 - 2016 CU23 Oct23SU 15.01.2507.034, 2019 Cumulative Update 1 15.02.0330.005 - 2019 RTM 15.02.0221.012

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External links
https://www.zerodayinitiative.com/advisories/ZDI-23-1578/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.