# CVE-2026-50143: Actor MCP path authority injection leaks Apify token

> A malicious Actor definition can redirect MCP client connections to an attacker-controlled host, leaking the victim's Apify API token and granting unauthorized access to data and compute resources.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N`)
- **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:** Yes
- **Published:** 18 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-6gr2-qh89-hxwm

## What is CVE-2026-50143?

CVE-2026-50143 is a high-severity server-side request forgery vulnerability in apify-mcp-server, published on 18 Aug 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

The Apify MCP server enables AI agents to extract data from websites using ready-made scrapers, crawlers, and automation tools available on the Apify Store. Prior to 0.10.11, getActorMCPServerURL in src/mcp/actors.ts concatenates the trusted Actor standby URL with the attacker-controlled webServerMcpPath from an Actor definition without verifying the resulting origin, allowing a malicious Actor publisher to use a userinfo-style authority value to redirect connectMCPClient to a third-party host. The call-actor, fetch-actor-details, and actor-mcp tool-loading paths pass this URL to transports in src/mcp/client.ts that attach the victim Authorization bearer token, exposing the Apify API token and enabling access to Actors, stored data, and billable compute. A victim must invoke or inspect the attacker-controlled Actor. This issue is fixed in version 0.10.11.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-50143?

2 open source packages ship an affected version, including @apify/actors-mcp-server.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@apify/actors-mcp-server` | npm | All versions | 0.10.11 |
| `@apify/actors-mcp-server` | npm | All versions | 0.10.11 |

## How do I fix CVE-2026-50143?

Upgrade @apify/actors-mcp-server to 0.10.11 or later.

## Is CVE-2026-50143 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50143 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-50143 and fix it if it is affected.

What it is: CVE-2026-50143 is a high-severity server-side request forgery vulnerability in apify-mcp-server, published on 18 Aug 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: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50143 exists.

Affected packages and fixed versions:
- @apify/actors-mcp-server (npm): affected all versions; fixed in 0.10.11
- @apify/actors-mcp-server (npm): affected all versions; fixed in 0.10.11

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-2026-50143/ (Markdown: https://insights.sbomify.com/CVE-2026-50143/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-50143
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-50143
- OSV: https://osv.dev/vulnerability/CVE-2026-50143

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-50143/
Summaries are generated and may contain mistakes; the official description above is the record.