CVE-2019-9875
KEVSitecore CMS and Experience Platform (XP) Deserialization Vulnerability
Description
Sitecore CMS and Experience Platform (XP) contain a deserialization vulnerability in the Sitecore.Security.AntiCSRF module that allows an authenticated attacker to execute arbitrary code by sending a serialized .NET object in the HTTP POST parameter __CSRFTOKEN.
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.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HPublishedMay 31, 2019
Last modifiedJun 17, 2026
Added to KEVMar 26, 2025
Remediation dueApr 16, 2025
References
- dev.sitecore.net/Downloads.aspxProductVendor Advisory
- synacktiv.com/blog.htmlThird Party Advisory
- synacktiv.com/ressources/advisories/Sitecore_CSRF_deserialize_RCE.pdfExploitPatch
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-9875US Government Resource
0 recent articles mention this CVE
77
Risk assessment · High
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 559 days
- CVSS
- 8.8 HIGH
- EPSS (30-day exploit probability)
- 25.4% · top 2% of all CVEs
- Weakness
- CWE-502
- Attack vector
- Network, remotely reachable
Recommended actions
- 1.Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.