CVE-2026-67543: Heym Unsandboxed skill code execution: skills run via a local backend subprocess without the Docker isolation that Python tools mandate
Noroxi assessment
Priority: Monitor (action score 35/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: heymrun heym 0.0.70.
Low priority for now. Upgrade to heymrun heym 0.0.70 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to version 0.0.70, heym hardens one untrusted-code path but not its sibling. The Python tool executor (python_tool_executor.py) treats user code as untrusted and mandates a Docker sandbox (no network, read-only fs, non-root, no docker socket), failing closed. The skill executor (skill_python_executor.py) runs skill Python via a local backend subprocess with no Docker isolation — only a 512 MB RLIMIT and a 7-key env denylist — so a skill executes inside the backend execution context, with filesystem access, network egress, and non-denylisted environment variables that should not be exposed to untrusted/shared skills. In the shipped Docker config (backend runs as root + /var/run/docker.sock mounted), this escalates to host root. This issue has been patched in version 0.0.70.
- Published
- Nov 11, 2026
- Updated
- Nov 11, 2026
- EPSS
- —
- CWE
- CWE-94
Report tools
Action score
35
Low priority for now.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · —
CNA vs NVD score
- NVD
- —
- CNA · GitHub_M
- 8.8
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
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Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
heymrun heym
- < 0.0.70affected
Same product
heymrun: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-67546Heym: Command execution via POST /api/mcp/fetch-tools stdio transport: supplied command is spawned before MCP validation35Monitor
- CVE-2026-67544Heym: Playwright Custom Code Backend RCE via `playwrightCode` Field35Monitor
- CVE-2026-55376heym Python Tool Sandbox Escape35Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-67541Nov 11, 2026 · Heym: Missing role gate in team-member management lets any member add/remove members, exposing team-shared credentials32Monitor
- ← EarlierCVE-2026-67542Nov 11, 2026 · Heym: SSRF via POST /api/mcp/fetch-tools: any authenticated user reaches local/private URLs through the SSE and streamable-HTTP transports28Monitor
- Later →CVE-2026-67545Nov 11, 2026 · Heym: Server-Side Request Forgery (SSRF) in HTTP Workflow Node29Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| heymrun heym | 0.0.70 · description | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 12, 2026same day
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-675440 days apartHeym: Playwright Custom Code Backend RCE via `playwrightCode` Field35Monitor
- CVE-2026-675460 days apartHeym: Command execution via POST /api/mcp/fetch-tools stdio transport: supplied command is spawned before MCP validation35Monitor
- CVE-2026-10086445 days apartheym before 0.0.91 Remote Code Execution via Expression Engine34Monitor
- CVE-2026-10086545 days apartHeym before 0.0.53 Remote Code Execution via eval() Sandbox Escape34Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
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Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-94 · Improper Control of Generation of Code ('Code Injection')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
Change log
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (3 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.