CVE-2026-50143 apify CVE debrief

Who should care

Defenders responsible for Apify MCP server deployments, users of Apify services, and security teams should assess exposure and verify Actor definitions to prevent potential exploitation. This includes reviewing the Apify MCP server access controls, verifying Actor definitions for suspicious activity, and ensuring that the server is updated to version 0.10.11 or later. Additionally, defenders should prioritize verifying Actor definitions and restricting  

Why it matters

Defenders should care about CVE-2026-50143 because it allows a malicious Actor publisher to redirect connectMCPClient to a third-party host, potentially exposing Apify API tokens and enabling unauthorized access to sensitive resources. Defenders responsible for Apify MCP server deployments and users of Apify services should assess exposure, verify Actor definitions, and prioritize updating to version 0.10.11 or later to prevent potential exploitation.

• Potential exposure of Apify API tokens
• Potential unauthorized access to Actors, stored data, and billable compute
• Need for verification of Actor definitions and MCP server access controls
• Priority for updating to version 0.10.11 or later

Technical summary

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.

Defensive priority

Defenders should prioritize verifying Actor definitions and restricting access to the Apify MCP server to prevent potential exploitation.

Recommended defensive actions

• Verify Actor definitions for suspicious webServerMcpPath values
• Restrict access to the Apify MCP server to trusted users and networks
• Monitor for unusual activity on the Apify MCP server
• Update to version 0.10.11 or later
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD vulnerability detail page provide information on the vulnerability, its impact, and the fixed version. Evidence is based on the official CVE Program record and NIST NVD detail page. The vulnerability has been fixed in version 0.10.11. Defenders should verify Actor definitions and restrict access to the Apify MCP server. The CVE record was published on 2026-08-18T18:17:53.227Z and has not been modified since then.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.