CVE-2026-100864: high-severity vulnerability in heymrun heym
heym before 0.0.91 Remote Code Execution via Expression Engine
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.9%
heym before 0.0.91 contains a sandbox escape vulnerability in the expression engine's DotList map/filter and fallback resolver that allows authenticated users to execute arbitrary Python code. Attackers can craft workflow expressions using dunder attribute access through item expressions or the fallback resolver to access os.system and execute commands as the backend process.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
heymrun · heymRelated CVEs — heymrun heym
In the same product, most dangerous first.
CVE-2026-55376HIGHheym Python Tool Sandbox EscapeEPSS 0.5%CVE-2026-100865HIGHHeym before 0.0.53 Remote Code Execution via eval() Sandbox EscapeEPSS 0.4%CVE-2026-101050HIGHHeym before 0.0.53 Authentication Bypass via Telegram WebhookEPSS 0.4%CVE-2026-101049HIGHHeym before 0.0.53 Slack Webhook Signature Verification BypassEPSS 0.4%CVE-2026-45225HIGHHeym < 0.0.21 Path Traversal File Upload via upload_file()EPSS 0.4%CVE-2026-84207MEDIUMHeym before 0.0.98 SSRF via WebSocket endpointsEPSS 0.3%