Zero-day vulnerability in Sitecore Experience Platform

Deserialization of Untrusted Data
CVE-2025-53690

Vulnerability details

Advisory: SB2025090436 - Remote code execution in Sitecore products

Vulnerable component: Sitecore Experience Platform

CVE-ID: CVE-2025-53690

CVSSv3 score: CVSS:3.1/AV:N/AC:H/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 in ViewState. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.

The vulnerability affects users who deployed any version of multiple Sitecore products using the sample key exposed in publicly available deployment guides (specifically Sitecore XP 9.0 and Active Directory 1.4 and earlier versions).

Note, the vulnerability is being actively exploited in the wild. 

External links:

https://cloud.google.com/blog/topics/threat-intelligence/viewstate-deserialization-zero-day-vulnerability

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.