๐Ÿ” CVE Alert

CVE-2026-100865

HIGH 8.8

Heym before 0.0.53 Multiple RCE and Authentication Bypass Vulnerabilities

CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th

Heym before 0.0.53 contains multiple independent vulnerabilities. (1) The workflow condition evaluator uses Python eval() without an effective sandbox, allowing any user who can edit a workflow branch/condition node โ€” or who can import a workflow template containing a malicious condition node โ€” to execute arbitrary Python code as the backend process user when the workflow runs. (2) Slack webhook signature verification and (3) Telegram webhook secret-token verification fail open when the trigger node has no credentialId or an empty signing secret, allowing anyone who knows the public webhook URL to trigger workflows with the owner's credentials without authentication. (4) The OAuth authorization endpoint does not validate the redirect_uri scheme, so an attacker who registers a public OAuth client with a javascript: or data: redirect_uri and lures a victim to the consent screen receives the authorization code and executes attacker-controlled JavaScript in the Heym origin, including access to the victim's HttpOnly auth cookie. (5) WorkflowExecutionToken, PortalSession, HITLRequest.public_token, and OAuthAuthorizationCode values are stored in plaintext, so any database read exposure yields valid scoped bearer tokens, including portal and HITL tokens with a 168-hour TTL that permit workflow execution on behalf of the owner.

CWE CWE-94
Vendor heymrun
Product heym
Published Sep 27, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

heymrun / heym
0 < 0.0.53

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/heymrun/heym/security/advisories/GHSA-pm6h-x3h5-j38h vulncheck.com: https://www.vulncheck.com/advisories/heym-before-0.0.53-multiple-rce-and-authentication-bypass-vulnerabilities

Credits

okcomputerfan mbakgun