Vulnerability · Published May 16, 2026 · Assigned by snyk

CVE-2026-8657

High 8.2

In plain English

A high-severity prototype pollution in jsondiffpatch. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.2High

Exploit odds (30 days)0.4%top 68.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	jsondiffpatch	0.7.6	GHSA-j4fx-xxwh-2485

Affected products (as reported)

Vendor	Product	Versions
n/a	jsondiffpatch	0 – before 0.7.6
n/a	org.webjars.npm:jsondiffpatch	0 – before *

Weakness: CWE-1321 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L/E:P

In plain English

Official description

Affected packages & fixed versions

Affected products (as reported)

References