CVE-2021-26707

Name: CVE-2021-26707
Creator: NVD / NIST
Published: 2021-06-02T15:15:07.787+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.90%

Last modified Jun 17, 2026

CVE-2021-26707 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 1.90% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.90%

77.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-1321

Affected Software

Vendor	Product	Versions
Merge-Deep Project	Merge-Deep	< 3.0.3
Netapp	E-Series Performance Analyzer	All versions

References

https://github.com/jonschlinkert/merge-deep/commit/11e5dd56de8a6aed0b1ed022089dbce6968d82a5Patch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20210716-0008/Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2020-160-merge-deep/Third Party Advisory
https://www.npmjs.com/package/merge-deepProduct, Third Party Advisory
https://github.com/jonschlinkert/merge-deep/commit/11e5dd56de8a6aed0b1ed022089dbce6968d82a5Patch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20210716-0008/Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2020-160-merge-deep/Third Party Advisory
https://www.npmjs.com/package/merge-deepProduct, Third Party Advisory

Timeline

Published: Jun 2, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-26707?

How severe is CVE-2021-26707?

CVE-2021-26707 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.90% probability of exploitation in the next 30 days.

How do I fix CVE-2021-26707?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-26707?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST