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


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
15.62% (97th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-MCPSERVERFETCH-17498918
  • published26 Jun 2026
  • disclosed26 Nov 2022

Introduced: 26 Nov 2022

CVE-2022-24999  (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.

qs before 6.10.3, as used in Express before 4.17.3 and other products, allows attackers to cause a Node process hang for an Express application because an __ proto__ key can be used. In many typical Express use cases, an unauthenticated remote attacker can place the attack payload in the query string of the URL that is used to visit the application, such as a[proto]=b&a[proto]&a[length]=100000000. The fix was backported to qs 6.9.7, 6.8.3, 6.7.3, 6.6.1, 6.5.3, 6.4.1, 6.3.3, and 6.2.4 (and therefore Express 4.17.3, which has "deps: qs@6.9.7" in its release description, is not vulnerable).

CVSS Base Scores

version 3.1