IRONSMITHINTEL
CRITICALCVSS9.0
|
Actively Exploited
|CISA KEV|CVE-2025-53690|Auth: none — unauthenticated|Reboot: required|Manual only

Sitecore Multiple Products Deserialization of Untrusted Data Vulnerability

Sitecore Experience Manager (XM), Experience Platform (XP), Experience Commerce (XC), and Managed Cloud contain a deserialization of untrusted data vulnerability involving the use of default machine keys. This flaw allows attackers to exploit exposed ASP.NET machine keys to achieve remote code execution.

Published Sep 3, 2025 · Updated May 16, 2026
Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2025-09-25 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Deserialization of Untrusted Data (CWE-502) vulnerability in Sitecore Multiple Products. Deserialization of Untrusted Data vulnerability in Sitecore Experience Manager (XM), Sitecore Experience Platform (XP) allows Code Injection.This issue affects Experience Manager (XM): through 9.0; Experience Platform (XP): through 9.0. Exploitation requires remote network access, higher attack complexity, no authentication required, and no user interaction required.

📧

Phishing link

🖼

Malicious file

🔓

Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

IT Security
Running experience commerce: v ≤ 9.0; experience manager: v ≤ 9.0; experience platform: v ≤ 9.0; managed cloud: -
Real-world incidentsWhat we've seen

Active exploitation documented in the wild. Threat-research write-up: https://cloud.google.com/blog/topics/threat-intelligence/viewstate-deserialization-zero-day-vulnerability

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

References

    1
    Vendor advisory: https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB1003865
    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2025-53690
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-53690
PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.