GHSA-37q6-576q-vgr7 · Severity: high · Ecosystem: npm — Missing Origin Validation in parcel-bundler
An issue was discovered in HMRServer.js in Parcel parcel-bundler. Attackers are able to steal developer's code because the origin of requests is not checked by the WebSocket server, which is used for HMR (Hot Module Replacement). Anyone can receive the HMR message sent by the WebSocket server via a ws://127.0.0.1 connection (with a random TCP port number) from any origin. The random port number can be found by connecting to http://127.0.0.1 and reading the "new WebSocket" line in the source code.
Conclusion & alert: CVE-2018-14731 is rated High Exploit Risk (75.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.33%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +2.09% over the last day, indicating growing attacker interest. Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
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 | 2026-06-15 | 0.23% | 2.33% | +2.09% |
| 2 | 2025-11-21 | 0.36% | 0.23% | -0.13% |
| 3 | 2025-11-18 | — | 0.36% | — |
Full EPSS history (13 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.0 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
GHSA-37q6-576q-vgr7 · Severity: high · Ecosystem: npm — Missing Origin Validation in parcel-bundler
| URL | Tags |
|---|---|
| https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages | Exploit Third Party Advisory |
| https://github.com/parcel-bundler/parcel/issues/1783 | Vendor Advisory |
| https://github.com/parcel-bundler/parcel/pull/1794 | Exploit Patch Vendor Advisory |