Security readout for executives and security teams
Plain-English summary
CVE-2019-9875 is a Sitecore remote code execution issue in the anti-CSRF module affecting versions through 9.1. An authenticated attacker could send malicious serialized .NET data in an HTTP POST parameter and run arbitrary code. CISA lists it as known exploited, so exposed legacy deployments need urgent review.
Executive priority
Treat this as urgent for any legacy Sitecore environment. It combines remote code execution impact with known exploitation and only requires authenticated access, making account misuse or compromised credentials a serious path to full application compromise.
Technical view
The issue is CWE-502 deserialization of untrusted data in Sitecore’s anti-CSRF module. CVSS 3.1 is 8.8 with network access, low complexity, low privileges, no user interaction, and high confidentiality, integrity, and availability impact. The provided record does not name a fixed version or detailed remediation steps.
Likely exposure
Organizations running Sitecore through 9.1 are the stated exposure group. Risk is highest where authenticated Sitecore functionality is reachable from untrusted networks or where low-privilege accounts exist broadly.
Exploitation context
CISA KEV inclusion supports known exploitation. Public source details indicate exploitation requires authenticated access and abuse of deserialization in an HTTP POST parameter. The provided bundle does not include exploit prevalence, affected deployment counts, or attacker targeting details.
Researcher notes
The source bundle supports Sitecore through 9.1, authenticated attack precondition, HTTP POST parameter deserialization, arbitrary code execution, CVSS 8.8, CWE-502, and KEV status. It does not provide a named patch version, IOC set, or safe product-specific validation procedure.
Mitigation direction
- Inventory all Sitecore deployments and identify versions through 9.1.
- Review Sitecore guidance and apply the vendor-supported update or remediation.
- Restrict authenticated Sitecore access to trusted networks where operationally possible.
- Review and reduce unnecessary Sitecore user accounts and privileges.
- Increase monitoring for anomalous authenticated POST activity and application errors.
Validation and detection
- Confirm whether any internet-facing Sitecore instance runs version 9.1 or earlier.
- Check Sitecore maintenance records against vendor download and advisory guidance.
- Verify only required users can authenticate to Sitecore management functionality.
- Review application logs for unusual authenticated requests around CSRF handling.
- Confirm compensating access controls are documented until vendor remediation is applied.
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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2019-9875 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
- High
- CVSS
- 8.8 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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:L/PR:L/UI:N/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://dev.sitecore.net/Downloads.aspxCVE reference · x_refsource_MISC
- https://www.synacktiv.com/blog.htmlCVE reference · x_refsource_MISC
- https://www.synacktiv.com/ressources/advisories/Sitecore_CSRF_deserialize_RCE.pdfCVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-9875CVE 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.