{"id":"CVE-2026-8657","state":"PUBLISHED","title":"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 attac","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.","publishedAt":"2026-05-16T05:00:09.867Z","updatedAt":"2026-08-23T15:25:14.637Z","severity":{"score":8.8,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:P","source":"snyk"},"assigner":"snyk","products":["n/a jsondiffpatch","n/a org.webjars.npm:jsondiffpatch"],"affected":[{"vendor":"n/a","product":"jsondiffpatch","versions":[{"version":"0","status":"affected","lessThan":"0.7.6","versionType":"semver"}]},{"vendor":"n/a","product":"org.webjars.npm:jsondiffpatch","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"semver"}]}],"references":["https://security.snyk.io/vuln/SNYK-JS-JSONDIFFPATCH-16322990","https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-16732792","https://gist.github.com/yuki-matsuhashi/e570fb1579ae1f3190059b622b0473fb","https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L82-L87","https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L107-L115","https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L146-L168","https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L171-L199","https://github.com/benjamine/jsondiffpatch/commit/381c0125efab49f6f0dbc08317d01d55717672af"],"weaknesses":["CWE-1321"],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/8xxx/CVE-2026-8657.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-8657","state":"PUBLISHED","datePublished":"2026-05-16T05:00:09.867Z","dateUpdated":"2026-08-23T15:25:14.637Z","assignerShortName":"snyk","assignerOrgId":"bae035ff-b466-4ff4-94d0-fc9efd9e1730","dateReserved":"2026-05-15T06:27:57.484Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"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":[{"vendor":"n/a","product":"jsondiffpatch","versions":[{"version":"0","status":"affected","lessThan":"0.7.6","versionType":"semver"}]},{"vendor":"n/a","product":"org.webjars.npm:jsondiffpatch","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"semver"}]}],"references":[{"url":"https://security.snyk.io/vuln/SNYK-JS-JSONDIFFPATCH-16322990"},{"url":"https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-16732792"},{"url":"https://gist.github.com/yuki-matsuhashi/e570fb1579ae1f3190059b622b0473fb"},{"url":"https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L82-L87"},{"url":"https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L107-L115"},{"url":"https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L146-L168"},{"url":"https://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L171-L199"},{"url":"https://github.com/benjamine/jsondiffpatch/commit/381c0125efab49f6f0dbc08317d01d55717672af"}],"metrics":[{"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","exploitCodeMaturity":"PROOF_OF_CONCEPT","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"LOW","baseScore":8.2,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L/E:P"},"cvssV4_0":{"version":"4.0","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:P"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1321","description":"Prototype Pollution","lang":"en"}]}],"providerMetadata":{"shortName":"snyk","orgId":"bae035ff-b466-4ff4-94d0-fc9efd9e1730","dateUpdated":"2026-08-23T15:25:14.637Z"},"credits":[{"value":"Yuki Matsuhashi","lang":"en"}]},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://gist.github.com/yuki-matsuhashi/e570fb1579ae1f3190059b622b0473fb","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-18T13:39:14.116160Z","id":"CVE-2026-8657","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1321","type":"CWE","lang":"en","description":"CWE-1321 Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-18T13:40:00.170Z"}}]}}}