CVE-2026-8657: jsondiffpatch patch APIs are vulnerable to prototype pollution
(updated )
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.
References
- gist.github.com/yuki-matsuhashi/e570fb1579ae1f3190059b622b0473fb
- github.com/advisories/GHSA-j4fx-xxwh-2485
- github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L107-L115
- github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L82-L87
- github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L146-L168
- github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L171-L199
- github.com/benjamine/jsondiffpatch/commit/381c0125efab49f6f0dbc08317d01d55717672af
- nvd.nist.gov/vuln/detail/CVE-2026-8657
- security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-16732792
- security.snyk.io/vuln/SNYK-JS-JSONDIFFPATCH-16322990
Code Behaviors & Features
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