Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to 0.0.40…
Summary
OS command injection reported (CVE-2026-55376). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 0.0.40 or later.
Original description
The description as published by the source.
Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to 0.0.40, an authenticated user who can create or edit a workflow with an Agent custom Python tool can bypass the blacklist-based sandbox in backend/app/services/python_tool_executor.py because allowed standard-library modules expose operating-system, process, and filesystem capabilities through public attributes that pass _safe_import() and _validate_code_safety(). The runner then executes the supplied tool with exec(), permitting commands and file operations as the backend application user; self-registration affects reachability, but portal triggering alone does not grant code control. This issue is fixed in 0.0.40.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-55376 has been found.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: upgrade the affected software to 0.0.40 or later.
If unsure, ask your IT team or search "CVE-2026-55376" on the vendor's site.
CVE-2026-55376 — CWE-78 / CVSS v3 8.8
Attack vector: remote (network-reachable) / no user interaction
Patched: 0.0.40 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
OS command injection (CWE-78) has been reported.
Check the vendor advisory for the affected versions.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to 0.0.40.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
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2Apply patch patch
Upgrade to 0.0.40ステージング環境で 0.0.40 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。