An issue was discovered in HMRServer.js in Parcel parcel-bundler
Published Sep 21, 2018
7.5
HIGHCVSS 3.0
EPSS 2.33%
Description
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.
Affected products
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
AV:N/AC:L/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v5
Table of values (17 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.33% (0.02327) | 82.89th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.33% (0.02327) | 81.22th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.19% (0.00187) | 56.36th | v3 (v2023.03.01) |
| Jul 6, 2024 | 0.19% (0.00187) | 56.19th | v3 (v2023.03.01) |
| May 10, 2024 | 0.27% (0.00265) | 66.01th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.29% (0.00293) | 68.29th | v3 (v2023.03.01) |
| Sep 15, 2023 | 0.29% (0.00293) | 65.47th | v3 (v2023.03.01) |
| Jul 8, 2023 | 0.33% (0.00327) | 66.83th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.28% (0.00280) | 63.42th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.95% (0.00954) | 36.37th | v2 (v2022.01.01) |
| Sep 2, 2022 | 0.95% (0.00954) | 34.50th | v2 (v2022.01.01) |
| Apr 1, 2022 | 0.95% (0.00954) | 32.50th | v2 (v2022.01.01) |
| Feb 4, 2022 | 0.95% (0.00954) | 16.28th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.88% (0.00884) | 25.39th | v1 |
| Jan 6, 2022 | 0.88% (0.00884) | 24.77th | v1 |
| Sep 1, 2021 | 0.88% (0.00884) | 59.15th | v1 |
| Apr 14, 2021 | 0.88% (0.00884) | 0.00th | v1 |
References (8)
- https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages x_refsource_MISCExploitThird Party Advisory
- https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages)
- https://github.com/advisories/GHSA-37q6-576q-vgr7 Advisory
- https://github.com/parcel-bundler/parcel/commit/066e0bf6bd26b15c78bd47df023452e4b20073e4
- https://github.com/parcel-bundler/parcel/issues/1783 x_refsource_CONFIRMVendor Advisory
- https://github.com/parcel-bundler/parcel/pull/1794 x_refsource_CONFIRMExploitPatchVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2018-14731
- https://www.npmjs.com/advisories/721
| Link | Providers | Tags |
|---|---|---|
| https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages | x_refsource_MISCExploitThird Party Advisory | |
| https://blog.cal1.cn/post/Sniffing%20Codes%20in%20Hot%20Module%20Reloading%20Messages) | ||
| https://github.com/advisories/GHSA-37q6-576q-vgr7 | Advisory | |
| https://github.com/parcel-bundler/parcel/commit/066e0bf6bd26b15c78bd47df023452e4b20073e4 | ||
| https://github.com/parcel-bundler/parcel/issues/1783 | x_refsource_CONFIRMVendor Advisory | |
| https://github.com/parcel-bundler/parcel/pull/1794 | x_refsource_CONFIRMExploitPatchVendor Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-14731 | ||
| https://www.npmjs.com/advisories/721 |
Change history (0)
No recorded changes yet.