Prototype pollution in Merge-deep
The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | merge-deep | < 3.0.3 | 3.0.3 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2021-26707
- https://github.com/jonschlinkert/merge-deep/commit/11e5dd56de8a6aed0b1ed022089dbce6968d82a5
- https://security.netapp.com/advisory/ntap-20210716-0008
- https://securitylab.github.com/advisories/GHSL-2020-160-merge-deep
- https://www.npmjs.com/package/merge-deep
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-1321- Platform
- npm
- Package
merge-deep- Disclosed
- 07.06.2021
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-r6rj-9ch6-g264 - CC BY 4.0
Vulnerability history: merge-deep
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 2
- First → latest
- 07.2018 06.2021
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 1
Disclosures per year
- 2018: 1
- 2019: 0
- 2020: 0
- 2021: 1
- 2022: 0
- 2023: 0
- 2024: 0
- 2025: 0
- 2026: 0
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Prototype pollution in Merge-deep this entry
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