Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') Affecting mcp-server-fetch package, versions *


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
3.83% (90th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-MCPSERVERFETCH-17663748
  • published29 Jun 2026
  • disclosed13 Nov 2021

Introduced: 13 Nov 2021

CVE-2021-3918  (opens in a new tab)
CWE-1321  (opens in a new tab)

How to fix?

There is no fixed version for Minimos:latest mcp-server-fetch.

NVD Description

Note: Versions mentioned in the description apply only to the upstream mcp-server-fetch package and not the mcp-server-fetch package as distributed by Minimos. See How to fix? for Minimos:latest relevant fixed versions and status.

json-schema is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

CVSS Base Scores

version 3.1