CVEs / CVE-2019-9875
CVE-2019-9875: Sitecore CMS and Experience Platform (XP) Deserialization Vulnerability
- Known exploited in the CISA KEV catalog since 26 Mar 2025
- high 8.8 CVSS 3.1 (NVD)
- EPSS 25.4% chance of exploitation in the next 30 days, higher than 97% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| n/a n/a | n/a | — |
Exploitation
| In CISA KEV since | 26 Mar 2025 |
|---|---|
| Due date for US federal agencies | 16 Apr 2025 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-502 |
References
- CVE-2019-9875 on NVD
- CVE-2019-9875 in the CISA KEV catalog
- https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB0038556 (cited by CISA)
- 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-2019-9875 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.