{"id":"CVE-2026-16266","state":"PUBLISHED","title":"Versions of the package mongo-object before 3.0.3 are vulnerable to Prototype Pollution via the expandKey() function in util.js. An attacker can modify the JavaScript prototype cha","description":"Versions of the package mongo-object before 3.0.3 are vulnerable to Prototype Pollution via the expandKey() function in util.js. An attacker can modify the JavaScript prototype chain by supplying a crafted property path containing special keys such as __proto__.","publishedAt":"2026-07-21T05:00:00.647Z","updatedAt":"2026-07-21T14:52:06.858Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","source":"snyk"},"assigner":"snyk","products":["n/a mongo-object"],"affected":[{"vendor":"n/a","product":"mongo-object","versions":[{"version":"0","status":"affected","lessThan":"3.0.3","versionType":"semver"}]}],"references":["https://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714","https://github.com/longshotlabs/mongo-object/issues/27","https://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251","https://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c"],"weaknesses":["CWE-1321"],"ingestedAt":"2026-10-29T20:11:00.674Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/16xxx/CVE-2026-16266.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-16266","state":"PUBLISHED","datePublished":"2026-07-21T05:00:00.647Z","dateUpdated":"2026-07-21T14:52:06.858Z","assignerShortName":"snyk","assignerOrgId":"bae035ff-b466-4ff4-94d0-fc9efd9e1730","dateReserved":"2026-07-20T08:55:21.686Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"Versions of the package mongo-object before 3.0.3 are vulnerable to Prototype Pollution via the expandKey() function in util.js. An attacker can modify the JavaScript prototype chain by supplying a crafted property path containing special keys such as __proto__."}],"affected":[{"vendor":"n/a","product":"mongo-object","versions":[{"version":"0","status":"affected","lessThan":"3.0.3","versionType":"semver"}]}],"references":[{"url":"https://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714"},{"url":"https://github.com/longshotlabs/mongo-object/issues/27"},{"url":"https://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251"},{"url":"https://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c"}],"metrics":[{"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"HIGH","exploitCodeMaturity":"NOT_DEFINED","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE","baseScore":4,"baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N"},"cvssV4_0":{"version":"4.0","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","baseScore":6.3,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1321","description":"Prototype Pollution","lang":"en"}]}],"providerMetadata":{"shortName":"snyk","orgId":"bae035ff-b466-4ff4-94d0-fc9efd9e1730","dateUpdated":"2026-07-21T05:00:00.647Z"},"credits":[{"value":"Dezhen Kong","lang":"en"}]},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/longshotlabs/mongo-object/issues/27","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-21T14:41:50.967466Z","id":"CVE-2026-16266","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-21T14:52:06.858Z"}}]}}}