Deserialization in Sitecore Cms

CVE-2019-9875

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.

Vulnerability class: Insecure Deserialization

EPSS: 0.142 (96.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

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.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2019-9875?
CVE-2019-9875 is a high-severity vulnerability in Sitecore Cms, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2019-05-31.
How severe is CVE-2019-9875?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2019-9875 known to be exploited?
Yes. CVE-2019-9875 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-03-26), indicating it is being actively exploited. 2 public proof-of-concept repositories are indexed.