CVE-2025-53691

HighPublic PoCRCE

Published: 03 September 2025

Published

03 September 2025

Modified

08 September 2025

KEV Added

—

Patch

—

CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0419 88.8th percentile

Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-53691 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Sitecore Experience Platform. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 11.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 RA-5 (Vulnerability Monitoring and Scanning) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Requires timely patching of the specific deserialization of untrusted data flaw in vulnerable Sitecore versions as detailed in KB1003667 to prevent RCE.

SI-10 Information Input Validation good match

prevent

Enforces validation of untrusted inputs to block malicious serialized data from being deserialized, directly countering CWE-502 exploitation.

RA-5 Vulnerability Monitoring and Scanning good match

detect

Scans for known vulnerabilities like CVE-2025-53691 in Sitecore XM/XP components to identify and prioritize remediation of affected instances.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

Why these techniques?

Direct RCE via deserialization in a public-facing web app (Sitecore XM/XP) maps to exploitation of exposed applications.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Deserialization of Untrusted Data vulnerability in Sitecore Experience Manager (XM), Sitecore Experience Platform (XP) allows Remote Code Execution (RCE).This issue affects Experience Manager (XM): from 9.0 through 9.3, from 10.0 through 10.4; Experience Platform (XP): from 9.0 through 9.3, from…

10.0 through 10.4.

Deeper analysisAI

CVE-2025-53691 is a Deserialization of Untrusted Data vulnerability (CWE-502) affecting Sitecore Experience Manager (XM) versions from 9.0 through 9.3 and 10.0 through 10.4, as well as Sitecore Experience Platform (XP) versions from 9.0 through 9.3 and 10.0 through 10.4. Published on 2025-09-03, it enables remote code execution (RCE) and carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact on confidentiality, integrity, and availability.

The vulnerability can be exploited by a remote attacker requiring low privileges (PR:L), such as an authenticated user, over the network with low complexity and no user interaction. Successful exploitation allows the attacker to achieve RCE, potentially leading to full compromise of the affected Sitecore instance.

Sitecore has issued a knowledge base article (KB1003667) providing details on the issue, likely including patches or mitigation guidance. Additional technical analysis is available from Watchtower Labs, which describes a cache poisoning vector leading to RCE in Sitecore Experience Platform. Security practitioners should consult these references for specific remediation steps.