CVE-2026-102615

    Dashboard / Vulnerabilities / CVE-2026-102615

    CVE-2026-102615

    Published: 5 Nov 2026Last Modified: 7 Nov 2026

    Summary: HeyForm: Uploaded HTML files are served as text/html on the app origin with no CSP — stored XSS

    Details: HeyForm is an open-source form builder. Prior to 3.0.1, /api/upload accepts a file according to the client-controlled multipart file.mimetype while retaining an HTML filename, and static/upload serves the resulting file as text/html with contentSecurityPolicy: false. An ordinary user can therefore upload active HTML that executes on the HeyForm origin when a victim opens its returned URL. The same-origin script can access /graphql with the victim's session and read or modify data available to that account. The code also permits upload requests tied to an active public form through formId, openToken, and a fieldId belonging to a file or signature question, although the advisory did not fully verify that unauthenticated path end to end. This issue is fixed in version 3.0.1.

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Affected versions

    v3.0.0
    v3.0.0-rc.10
    v3.0.0-rc.9
    v3.0.0-rc.8
    v3.0.0-rc.7
    v3.0.0-rc.6
    v3.0.0-rc.5
    v3.0.0-rc.4
    v3.0.0-rc.3
    v3.0.0-rc.2
    v3.0.0-rc.1
    v3.0.0-alpha.3
    v3.0.0-alpha-2

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2026-102615 | CVE-DB