CVE-2021-26707

highpriority · track · 40EPSS 0.019 · 80 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.92% (80th) EPSS

CVSS 7.5 · high

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-28

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.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · OSV

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1321USprimaryCWE-1321US

affected products (4)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
merge-deep project merge-deep< 3.0.3nvdUScpe:2.3:a:merge-deep_project:merge-deep:*:*:*:*:*:*:*:*
netapp e-series performance analyzerall versionsnvdUScpe:2.3:a:netapp:e-series_performance_analyzer:*:*:*:*:*:*:*:*
npm merge-deep< 3.0.3osvUSpkg:npm/merge-deep

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-r6rj-9ch6-g264Prototype pollution in Merge-deep2021-06-07ghsa · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-06-02modified 2026-06-17

related (708)

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+703 more

references (13)

External citations — patches, advisories, analysis.

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