CVE-2019-9875
HighExploitedPublic exploitDeserialization 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.
Published May 31, 2019 · Updated Nov 7, 2025
Key Facts
Patch immediately- CVE-2019-9875 is a high-severity vulnerability (CVSS 8.8 v3.1) affecting CMS (Sitecore).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 26, 2025. Public exploit code is available.
- EPSS estimates a 14% probability of exploitation in the next 30 days.
- Fixed versions are available, including CMS <=9.1, CMS 9.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
8.8
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
14%
Higher than 96.4% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2019-9875 brief as a PDF
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Mar 26, 2025 | Apr 16, 2025 | Not reported |
| Industry KEV feed | Mar 26, 2025 | Apr 16, 2025 | Not reported |
| CIRCL KEV | Mar 26, 2025 | Apr 16, 2025 | Not reported |
| ENISA EUVD | Mar 26, 2025 | n/a | Not reported |
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.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| CMSSitecore | See advisory | 9.1 |
Patched Releases
CMS
<=9.1
Timeline
Publicly disclosed
May 31, 2019
Added to CISA KEV
Mar 26, 2025
Added to Industry KEV feed
Mar 26, 2025
Added to CIRCL KEV
Mar 26, 2025
Added to ENISA EUVD
Mar 26, 2025
Last updated
Nov 7, 2025
Weakness Type
- CWE-502 Deserialization of Untrusted Data
References
- advisoryhttps://dev.sitecore.net/Downloads.aspx
- advisoryhttps://www.synacktiv.com/blog.html
- patchhttps://www.synacktiv.com/ressources/advisories/Sitecore_CSRF_deserialize_RCE.pdf
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
FAQ
Common Questions.
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: CMS (Sitecore). The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 26, 2025.
Yes. It was added on Mar 26, 2025 with a federal remediation due date of Apr 16, 2025.
Public exploit code is available.
Fixed versions are available, including CMS <=9.1, CMS 9.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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