Horizon Alert
Summary of the vulnerability and why it matters
A vulnerability exists in the HeyForm form builder that could allow a user with limited access to take over an entire account. This occurs when a malicious script is injected into a form and then executed by an account owner viewing the form, potentially granting the attacker elevated privileges.
- Injected scripts can lead to account takeover.
- Protects against unauthorized privilege escalation.
- Confirm relevance and understand potential exposure.
Attack Path
How an attacker could exploit the issue
An attacker with low privileges could inject malicious JavaScript into a form created with HeyForm. This script would then execute when a team owner reviews the form, potentially allowing the attacker to take over the owner's account by escalating their own privileges.
- Low-privileged user access required.
- Malicious script injected into form.
- Account takeover via privilege escalation.
Live Threat
Current exploitation, exposure, and threat context
A stored cross-site scripting vulnerability in HeyForm's form builder could allow a low-privileged team member to inject malicious JavaScript. This script would execute when a team owner views the form, potentially leading to account takeover through privilege escalation when supported by the advisory.
- Team owner accounts at risk.
- Malicious script execution via form viewing.
- Complete account takeover possible.
Operational Fix
Recommended remediation, mitigation, and detection steps
Application owners responsible for HeyForm deployments must first confirm where this open-source form builder exists within their environment, verify its reachability and criticality, and identify the accountable parties before planning remediation. Coordination with the vendor or an internal platform team may be necessary to understand the available patches or mitigation strategies and schedule necessary updates during approved maintenance windows.
- Application owners should own this issue.
- Verify HeyForm reachability and criticality first.
- Plan remediation and coordinate vendor updates.
