Tophat is a mobile applications testing harness. Prior to 2.5.1, Tophat is affected by remote code execution via crafted tophat:// or http://localhost:29070 URLs. The arguments query parameter flows unsanitized from URL parsing through to /bin/bash -c execution, allowing an attacker to execute arbitrary commands on a developer's macOS workstation. Any developer with Tophat installed is vulnerable. For previously trusted build hosts, no confirmation dialog appears. Attacker commands run with the user's permissions. This vulnerability is fixed in 2.5.1.
Conclusion & alert: CVE-2026-39862 is rated Moderate Risk (43.8/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.30%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-21 | 0.45% | 0.30% | -0.15% |
| 2 | 2026-04-09 | — | 0.45% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.3 | 4.0 | MEDIUM |
|
— | — | [email protected] |
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| URL | Tags |
|---|---|
| https://github.com/Shopify/tophat/pull/139 | Issue Tracking |
| https://github.com/Shopify/tophat/security/advisories/GHSA-8x8g-6rv5-mgg2 | Vendor Advisory |