Historical catalog analysis: CISA added this entry on September 04, 2025. The entry reflects catalog information retrieved on August 31, 2026, not a snapshot archived on the inclusion date. Check current vendor guidance before acting.
What the vulnerability is
CVE-2025-53690 is a deserialization of untrusted data vulnerability (CWE-502) affecting multiple Sitecore products. The flaw stems from the use of default machine keys within ASP.NET. If an attacker can exploit these exposed default keys, they may achieve remote code execution (RCE) on the affected system.
Exposure and applicability
This vulnerability applies to organizations deploying the following Sitecore products:
* Experience Manager (XM)
* Experience Platform (XP)
* Experience Commerce (XC)
* Managed Cloud
The exposure is specifically tied to the configuration of ASP.NET machine keys. Systems utilizing default keys are susceptible, as these keys provide the necessary cryptographic material for an attacker to craft malicious serialized payloads that the application will trust and execute.
Remediation priorities
Based on our analysis, vulnerability management teams should prioritize the following actions:
- Identify Default Key Usage: Audit all Sitecore instances to determine if default machine keys are currently in use. This is the primary indicator of exposure.
- Apply Vendor Mitigations: Implement the corrective actions provided in the vendor’s official instructions to replace default keys with unique, secure keys.
- Cloud Service Review: For those utilizing Managed Cloud services, review configurations against BOD 22-01 guidance to ensure cloud-specific security requirements are met.
- Decommissioning: If mitigations cannot be applied or are unavailable for a specific legacy deployment, the product should be discontinued to eliminate the RCE vector.
How to validate remediation
Verification must go beyond a simple version check of the Sitecore software, as this vulnerability is rooted in configuration (machine keys) rather than just binary versions.
To verify that exposure has been reduced, defenders should provide evidence that the default machine keys have been replaced with unique values. Validation is achieved when the active configuration files or environment settings no longer contain the known default strings provided by the vendor. A successful mitigation is confirmed only when the specific cryptographic secret used for deserialization is verified as non-default and unique to the environment.
Limits and open questions
While replacing default keys addresses the immediate entry path described in CVE-2025-53690, residual risk remains if the new keys are stored insecurely or leaked. It is currently unknown whether this vulnerability has been utilized in known ransomware campaigns. Furthermore, the effectiveness of these mitigations depends on the correct implementation of the vendor’s instructions; improper key rotation could lead to application instability or incomplete remediation.
Source and editorial note
CVE-2025-53690: Sitecore Multiple Products Deserialization of Untrusted Data Vulnerability · Source date: September 04, 2025 · Retrieved August 31, 2026.
Material facts are tied to the cited primary source. Recommendations are independent defensive analysis unless attributed to the source. Confirm consequential decisions against current authoritative guidance.
Archive date: September 07, 2025. The displayed post date is assigned three days after the source date to organize this retrospective archive; it does not mean this site published the analysis then. First published by this site: October 03, 2026 at 00:23 UTC.
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