Vulnerability in Heymrun Heym
CVE-2026-100862
heym, a workflow automation platform, stores and returns multiple capability secrets in plaintext in versions prior to 0.0.91. Affected secrets include webhook header-auth values (returned in cleartext by GET /api/workflows/{id} and persisted unsanitized into execution history), MCP API keys (stored as a plaintext column, returned in config/list responses, and accepted via the ?key= query string so they leak into logs, proxies and Referer headers), portal session tokens (stored and validated by plaintext equality with a 168-hour TTL), workflow execution JWTs (stored in full and re-listed by GET .../execution-tokens), Discord interaction tokens (the full interaction body is stored in execution history), and global variables. A user with read access to a workflow, share/team membership, or anyone able to read the database, a backup, or logs can recover these secrets and replay them to execute workflows or act as the secret owner.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.002 (9.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-6x65-w7q7-wg93) (vendor-advisory)
- VulnCheck Advisory: heym before 0.0.91 Multiple Secrets Plaintext Storage (third-party-advisory)
Frequently asked questions
- What is CVE-2026-100862?
- CVE-2026-100862 is a medium-severity vulnerability in Heymrun Heym, classified under Cleartext Storage of Sensitive Information. CVSS score: 4.9/10. Published 2026-09-27.
- How severe is CVE-2026-100862?
- Medium severity. CVSS v3 base score is 4.9 out of 10.