{"id":"CVE-2026-8161","state":"PUBLISHED","title":"multiparty vulnerable to Denial of Service via Prototype Pollution leading to Uncaught Exception","description":"multiparty@4.2.3 and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to multiparty@4.3.0 or higher.","publishedAt":"2026-05-12T08:50:37.685Z","updatedAt":"2026-05-12T12:32:10.127Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"openjs"},"assigner":"openjs","products":["multiparty multiparty"],"affected":[{"vendor":"multiparty","product":"multiparty","packageURL":"pkg:npm/multiparty","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"4.2.3","versionType":"semver"},{"version":"4.3.0","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/pillarjs/multiparty/security/advisories/GHSA-qxch-whhj-8956","https://cna.openjsf.org/security-advisories.html"],"weaknesses":["CWE-248","CWE-1321"],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/8xxx/CVE-2026-8161.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-8161","state":"PUBLISHED","datePublished":"2026-05-12T08:50:37.685Z","dateUpdated":"2026-05-12T12:32:10.127Z","assignerShortName":"openjs","assignerOrgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateReserved":"2026-05-08T10:38:20.438Z"},"containers":{"cna":{"title":"multiparty vulnerable to Denial of Service via Prototype Pollution leading to Uncaught Exception","descriptions":[{"lang":"en","value":"multiparty@4.2.3 and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to multiparty@4.3.0 or higher."}],"affected":[{"vendor":"multiparty","product":"multiparty","packageURL":"pkg:npm/multiparty","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"4.2.3","versionType":"semver"},{"version":"4.3.0","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/pillarjs/multiparty/security/advisories/GHSA-qxch-whhj-8956"},{"url":"https://cna.openjsf.org/security-advisories.html"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseSeverity":"HIGH","baseScore":7.5,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-248","lang":"en","description":"CWE-248: Uncaught Exception","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1321","lang":"en","description":"CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","type":"CWE"}]}],"providerMetadata":{"shortName":"openjs","orgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateUpdated":"2026-05-12T08:50:37.685Z"},"credits":[{"lang":"en","value":"Ser0n-ath","type":"reporter"},{"lang":"en","value":"Sebastian Beltran","type":"remediation developer"},{"lang":"en","value":"kq5y","type":"finder"},{"lang":"en","value":"Byambadalai Sumiya","type":"finder"},{"lang":"en","value":"Blake Embrey","type":"remediation reviewer"},{"lang":"en","value":"Ulises Gascón","type":"remediation reviewer"}],"x_generator":{"engine":"cve-kit 1.0.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-12T12:31:39.867190Z","id":"CVE-2026-8161","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-12T12:32:10.127Z"}}]}}}