# CVE-2019-9875: Sitecore CMS and Experience Platform (XP) Deserialization

> An authenticated attacker can execute arbitrary code in Sitecore by sending a malicious serialized .NET object via HTTP POST.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 26 Mar 2025 (CISA KEV)
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 May 2019
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-7gvq-j6pg-875g

## What is CVE-2019-9875?

CVE-2019-9875 is a high-severity unsafe deserialization vulnerability in n/a, published on 31 May 2019. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2019-9875?

It affects 1 product.


Products: Sitecore Cms.

## How do I fix CVE-2019-9875?

No fix has been published for CVE-2019-9875 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 16 Apr 2025.

## Is CVE-2019-9875 being exploited?

Yes. Attackers have exploited CVE-2019-9875 in the wild since at least 26 Mar 2025.

## Other vulnerabilities in n/a

- [CVE-2019-9874](https://insights.sbomify.com/CVE-2019-9874/): Sitecore CMS and Experience Platform (XP) Deserialization (critical 9.8, exploited in the wild)
- [CVE-2019-11198](https://insights.sbomify.com/CVE-2019-11198/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2017-11439](https://insights.sbomify.com/CVE-2017-11439/): In Sitecore 8.2, there is reflected XSS in the shell/Applications/Tools/Run Program parameter. (medium 5.4)
- [CVE-2017-11440](https://insights.sbomify.com/CVE-2017-11440/): In Sitecore 8.2, there is absolute path traversal via the shell/Applications/Layouts/IDE.aspx fi parameter and the admin/LinqScratchPad.aspx Reference parameter. (medium 4.9)
- [CVE-2014-100004](https://insights.sbomify.com/CVE-2014-100004/): Cross-site scripting in n/a (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-9875 and fix it if it is affected.

What it is: CVE-2019-9875 is a high-severity unsafe deserialization vulnerability in n/a, published on 31 May 2019. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2019-9875 in the wild since at least 26 Mar 2025.

Affected product: n/a. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2019-9875/ (Markdown: https://insights.sbomify.com/CVE-2019-9875/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-9875
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-9875
- OSV: https://osv.dev/vulnerability/CVE-2019-9875

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-9875/
Summaries are generated and may contain mistakes; the official description above is the record.