Security readout for executives and security teams
Plain-English summary
CVE-2025-53690 is a critical Sitecore vulnerability that can let an unauthenticated attacker inject code through unsafe ViewState deserialization. It affects Sitecore Experience Manager and Experience Platform through version 9.0. CISA KEV confirms known exploitation, so exposed legacy Sitecore systems should be treated as urgent.
Executive priority
Treat this as an immediate remediation item for any legacy Sitecore XM or XP environment. Known exploitation and potential code injection create material business risk, especially where public websites connect to customer data, marketing operations, or internal systems.
Technical view
The issue is CWE-502 deserialization of untrusted data in Sitecore XM and XP through 9.0. The CVSS 3.1 score is 9.0 with network attack vector, no privileges, no user interaction, high impact, and high attack complexity. The reported impact is code injection.
Likely exposure
Organizations running Sitecore Experience Manager or Experience Platform through 9.0 are the stated exposure group. Internet-facing Sitecore deployments are the highest-priority validation target. The source bundle does not identify other affected Sitecore products or later versions.
Exploitation context
Active exploitation is supported by CISA KEV and the Google Cloud threat-intelligence reference describing a ViewState deserialization zero-day. The provided sources do not include exploit mechanics, attacker volume, or complete indicators in this bundle.
Researcher notes
Evidence supports critical severity, known exploitation, and affected Sitecore XM/XP through 9.0. The bundle does not provide patch version details, workaround specifics, exploit indicators, or proof that later versions are affected. Use vendor guidance for exact remediation.
Mitigation direction
- Inventory all Sitecore XM and XP deployments and record exact versions.
- Prioritize systems running Sitecore XM or XP through 9.0.
- Follow Sitecore KB1003865 for vendor-approved fixes or mitigations.
- Reduce external exposure for affected systems while remediation is underway.
- Monitor CISA KEV and Sitecore guidance for updated remediation deadlines.
Validation and detection
- Confirm whether any Sitecore XM or XP instance is version 9.0 or earlier.
- Identify which Sitecore systems are internet-facing or externally reachable.
- Review vendor guidance in Sitecore KB1003865 against each deployment.
- Check incident-response telemetry for suspicious activity on affected Sitecore hosts.
- Track remediation status separately for production, staging, and legacy systems.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-53690 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H2.26Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9CriticalVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://cloud.google.com/blog/topics/threat-intelligence/viewstate-deserialization-zero-day-vulnerabilityCVE reference
- https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB1003865CVE reference
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-53690CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.