{"schemaVersion":3,"id":"CVE-2021-3645","aliases":["GHSA-cqqh-49mx-fq63"],"status":"published","duplicateOf":null,"title":null,"description":"merge is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","dates":{"published":"2021-09-10T11:04:25.000Z","modified":"2024-08-03T17:01:07.653Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.8,"severity":"critical","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.0","versionLabel":"v3.0","source":"CVE.org","score":6.8,"severity":"medium","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Npm","score":9.8,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":10,"impact":9.8,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":9.8,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.0","versionLabel":"v3.0","source":"NVD","score":6.8,"severity":"medium","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":7.5,"severity":"high","vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.01429,"percentile":0.72642,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.01429},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01429,"percentile":0.72642}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01429,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01429,"percentile":0.72642}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[{"id":"REF_F622DF162EC2B5CD","name":"Exploit Reference (huntr.dev)","source":"reference","url":"https://huntr.dev/bounties/ef387a9e-ca3c-4c21-80e3-d34a6a896262","maturity":"unknown","reliabilityScore":0.2,"verified":false,"type":null,"platforms":[],"requiresAuth":null,"exploitdb":null,"metasploit":null}],"exploitCount":1,"weaknesses":[{"id":"CWE-1321","name":"Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","description":"The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.","type":"weakness","status":"Incomplete","abstraction":"Variant","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/1321.html"}],"affected":[{"vendor":"merge_project","product":"merge","name":"merge","label":"merge","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.0.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.0.2","eol":null,"hubHref":"/vendor/merge_project/merge"},{"vendor":"@viking04","product":"merge","name":"@viking04/merge","label":"merge","ecosystem":"Npm","cpePart":null,"purl":"pkg:npm/@viking04/merge","purlType":"npm","versions":[{"text":"< 1.0.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.0.2","eol":null,"hubHref":null},{"vendor":"viking04","product":"viking04/merge","name":"viking04/merge","label":"viking04/merge","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ unspecified, < 1.0.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ unspecified, < 1.0.2","eol":null,"hubHref":"/vendor/viking04/viking04merge"}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://huntr.dev/bounties/ef387a9e-ca3c-4c21-80e3-d34a6a896262","label":"huntr.dev/bounties/ef387a9e-ca3c-4c21-80e3-d34a6a896262","hostname":"huntr.dev","tags":["X Refsource CONFIRM","WEB","Exploit","Third Party Advisory"]},{"url":"https://github.com/viking04/merge/commit/baba40332080b38b33840d2614df6d4142dedaf6","label":"github.com/viking04/merge/commit/baba40332080b38b33840d2614df6d4142dedaf6","hostname":"github.com","tags":["X Refsource MISC","WEB","Patch","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-3645","label":"nvd.nist.gov/vuln/detail/CVE-2021-3645","hostname":"nvd.nist.gov","tags":["Advisory"]},{"url":"https://github.com/viking04/merge","label":"github.com/viking04/merge","hostname":"github.com","tags":["PACKAGE"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-09-10T11:04:25.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-08-03T17:01:07.653Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T18:21:54.829Z","stale":false,"partial":false}}