Deserialization of Untrusted Data in the anti CSRF module in Sitecore through 9.1 allows an authenticated attacker to execute arbitrary code by sending a serialized .NET object in an HTTP POST parameter.
Why It Matters
Analysis dossierWhy It Matters
Deserialization of Untrusted Data in the anti CSRF module in Sitecore through 9.1 allows an authenticated attacker to execute arbitrary code by sending a serialized .NET object in an HTTP POST parameter.
Immediate Attention
Yes
Unknown
Risk basis: CISA KEV exploitation signal; HIGH severity; Known exploitation signal from CISA KEV or ransomware metadata
Affected Products & Remediation
1 source-backed product- sitecore cms · <= 9.1 · NVD CPE · Source
Vendor or catalog guidance (source)
- CISA KEV: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Listed
- Exploited (source statement)
- Yes
- Publicly disclosed (source)
- Unknown
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.
Suggested hunting (rule-based inference)
SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.
Matched kev-network-exposure (CVSS AV:N, CISA KEV Listed); deserialization (CWE-502)
Exposure
- Identify assets with the exact CVE and confirm the affected product/version against the advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · KEV listing raises urgency, but inventory is needed to establish local exposure. · Rule kev-network-exposure
- Find installations of the affected component and confirm the source-stated version range.Telemetry: Application inventory · Deserialization risk requires component and version evidence. · Rule deserialization
Exploitation evidence
- Review relevant edge or application access logs for unusual requests around the advisory window.Telemetry: CommonSecurityLog · Log review is a hunting hypothesis; KEV listing alone does not show local exploitation. · Rule kev-network-exposure
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Exploitation evidence
- Review unusual child processes or network connections from the affected service.Telemetry: DeviceProcessEvents · Unexpected behavior may support investigation but is not proof by itself. · Rule deserialization
Response
- Recheck the affected assets after the source-stated mitigation or update is applied.Telemetry: DeviceTvmSoftwareVulnerabilities · A follow-up inventory check verifies local remediation. · Rule kev-network-exposure
CISA KEV Record
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Change History & Source Data
— No recorded material change
- CNA / source
- cve@mitre.org
- Record status · verification
- UPDATED · CISA KEV confirmed
- CPE
- cpe:2.3:a:sitecore:cms:*:*:*:*:*:*:*:*
Evidence & Provenance
Linked by the query's stored exact CVE association. Review required tables and validation status before use.
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2019-9875"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel desc