CVE-2026-8657

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data tampering.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-16 06:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-07-05 16:19 UTC Last updatedMost recent change to the record

Details

Published

2026-05-16 06:16 UTC

Last modified

2026-07-05 16:19 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-1321 · Prototype pollution

Record status

Deferred

Attack profile CVSS 4.0 · 7.8

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

None

User interaction

None

Confidentiality

None

Integrity

High

Availability

Low