Zero-day vulnerability in Microsoft SharePoint Server

Deserialization of Untrusted Data
CVE-2025-53770

Not patched

Vulnerability details

Advisory: SB2025072001 - Remote code execution in Microsoft SharePoint Server

Vulnerable component: Microsoft SharePoint Server

CVE-ID: CVE-2025-53770

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C

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

Description:

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

The vulnerability exists due to insecure input validation when processing serialized data. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.

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

Note, the vulnerability is being exploited in the wild. 

External links:

https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2025-53770

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.