Deserialization of Untrusted Data in the Sitecore.Security.AntiCSRF (aka anti CSRF) module in Sitecore CMS 7.0 to 7.2 and Sitecore XP 7.5 to 8.2 allows an unauthenticated attacker to execute arbitrary code by sending a serialized .NET object in the HTTP POST parameter __CSRFTOKEN.
Conclusion & alert: CVE-2019-9874 is rated Critical Active Threat (100/100): CVSS Critical severity, with high exploitation likelihood (EPSS 87.63%, 99th percentile). Core evidence: CISA KEV confirms active exploitation (added 2025-03-26) affecting Sitecore / CMS and Experience Platform (XP). a weakness (CWE-502) Unauthenticated remote administrative access may be possible. EPSS rose +8.32% over the last day, indicating growing attacker interest. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
: Sitecore CMS and Experience Platform (XP) Deserialization Vulnerability · CISA KEV detail
: 2025-03-26
: 2025-04-16
: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-04 | 79.31% | 87.63% | +8.32% |
| 2 | 2026-05-01 | 79.70% | 79.31% | -0.40% |
| 3 | 2026-03-16 | — | 79.70% | — |
Full EPSS history (34 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.1 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
| 9.8 | 3.1 | CRITICAL |
|
3.9 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| sitecore | cms | >= 7.0, <= 7.2 | cpe:2.3:a:sitecore:cms:*:*:*:*:*:*:*:* |
| sitecore | experience_platform | >= 7.5, <= 8.2 | cpe:2.3:a:sitecore:experience_platform:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://dev.sitecore.net/Downloads.aspx | Product Vendor Advisory |
| https://www.synacktiv.com/blog.html | Third Party Advisory |
| https://www.synacktiv.com/ressources/advisories/Sitecore_CSRF_deserialize_RCE.pdf | Exploit Patch Third Party Advisory |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-9874 | US Government Resource |