# CVE-2026-9191: Insufficient isolation of user-supplied code in Progress MarkLogic Server

> Attackers can execute unauthorized code via REST/XDBC paths, compromising sessions and performing actions in MarkLogic Server.

- **Severity:** Critical 9.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 12 Oct 2026
- **Updated:** 14 Oct 2026
- **Also known as:** GHSA-gr4w-j394-9q4x

## What is CVE-2026-9191?

CVE-2026-9191 is a critical code injection vulnerability in Progress Software Corporation MarkLogic Server, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Progress MarkLogic Server 12.x releases before 12.1.0 and 11.x releases before 11.3.7 do not sufficiently isolate user-supplied code executed through certain REST and XDBC evaluation paths from HTTP request, response, and session state. An attacker able to execute code through an affected path could perform unauthorized actions or compromise an authenticated session.

Weakness: CWE-346 (Origin Validation Error)

## Which versions are affected by CVE-2026-9191?


## How do I fix CVE-2026-9191?

No fix has been published for CVE-2026-9191 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-9191 being exploited?

There is no known exploitation of CVE-2026-9191 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-9191 and fix it if it is affected.

What it is: CVE-2026-9191 is a critical code injection vulnerability in Progress Software Corporation MarkLogic Server, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-9191 in the wild and no public exploit code.

Affected product: Progress Software Corporation MarkLogic Server. 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-2026-9191/ (Markdown: https://insights.sbomify.com/CVE-2026-9191/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-9191
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-9191
- OSV: https://osv.dev/vulnerability/CVE-2026-9191

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-9191/
Summaries are generated and may contain mistakes; the official description above is the record.