# CVE-2026-67544: Heym: Playwright Custom Code Backend RCE via `playwrightCode` Field

Status: published. Published: 2026-11-11. Updated: 2026-11-11.

Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to version 0.0.71, Heym's workflow engine accepts an arbitrary Python code string in the playwrightCode field of a Playwright node. This string is written to a temporary .py file and executed directly by the backend process via subprocess.Popen([sys.executable, script_path]) with no sandboxing, AST validation, or role gate. Any authenticated user — including a freshly registered account — can achieve full remote code execution (RCE) on the backend host, running as the service process user (observed as root in the default Docker deployment). This issue has been patched in version 0.0.71.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- heymrun / heym: < 0.0.71 (affected). Source: CNA: GitHub_M

## Severity and prioritization

- CVSS 3.1: 8.8 (high); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: CNA: GitHub_M

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-94

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/heymrun/heym/security/advisories/GHSA-mp23-7m6r-jfw4 (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/heymrun/heym/commit/d2fd46c07754c4ed3e80b521aa54cc276039849b (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/heymrun/heym/releases/tag/0.0.71 (CNA: GitHub_M; x_refsource_MISC)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-67544; retrieved 2026-11-11; source updated 2026-11-11

Revision: 1042a030e56bbd537a33ec830cfda8d49d62c400cd8c3ec2de9b966c0374a6bf

Canonical: https://y2.dev/cve/CVE-2026-67544

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.