CVE WatchJul 5, 2026

CVE-2026-8657

Versions of the package jsondiffpatch before 0.7.6 are vulnerable to Prototype Pollution via the jsondiffpatch.patch() and jsondiffpatch/for

CVSS

8.2

High

EPSS

0.4%

p32

KEV

—

Exploit Today

0-100

Published: May 16, 2026 · Last modified: Jul 5, 2026 · CWE-1321

EPSS · 30d

0.4%EPSS · 30 days0.4%

2026-08-232026-09-20

Technical description

Versions of the package jsondiffpatch before 0.7.6 are vulnerable to Prototype Pollution via the jsondiffpatch.patch() and jsondiffpatch/formatters/jsonpatch.patch() APIs. An attacker can perform prototype pollution by supplying crafted delta or JSON Patch documents, as attacker-controlled property names and path segments are used to traverse and modify objects without restricting access to special properties like __proto__ or constructor.prototype, allowing modification of Object.prototype.

Official references

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