{"id":"CVE-2026-49982","summary":"tmp: Type-confusion bypass of _assertPath in tmp@0.2.6 allows path traversal via non-string prefix/postfix/template","details":"tmp is a temporary file and directory creator for node.js. In version 0.2.6, the _assertPath guard added to tmp rejects only string values that contain the substring ... It is bypassed when prefix, postfix, or template is supplied as a non-string value (Array, Buffer, or any object) whose includes('..') returns falsy but whose stringification still contains ../. The value flows through Array.prototype.join/String coercion inside _generateTmpName and path.join(tmpDir, opts.dir, name), producing a final path that escapes tmpdir and creates a file or directory at an attacker-controlled location with the host process's privileges. This affects any application that forwards untrusted request data (a common pattern is JSON body fields or qs-parsed bracket-array query strings such as ?prefix[]=...) into tmp.file, tmp.fileSync, tmp.dir, tmp.dirSync, tmp.tmpName, or tmp.tmpNameSync without explicit type coercion. This vulnerability is fixed in 0.2.7.","aliases":["GHSA-7c78-jf6q-g5cm"],"modified":"2026-07-08T08:09:43.199657542Z","published":"2026-06-11T15:45:00.685Z","related":["CGA-6j9p-77c7-v873"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49982.json","cwe_ids":["CWE-20","CWE-22"],"cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49982.json"},{"type":"ADVISORY","url":"https://github.com/raszi/node-tmp/security/advisories/GHSA-7c78-jf6q-g5cm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49982"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/raszi/node-tmp","events":[{"introduced":"41f71598d03f104a67e0448a7cb9bd4efcdd5980"},{"last_affected":"41f71598d03f104a67e0448a7cb9bd4efcdd5980"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_STRING"],"cpe":"cpe:2.3:a:raszi:tmp:0.2.6:*:*:*:*:node.js:*:*","extracted_events":[{"introduced":"0.2.6"},{"last_affected":"0.2.6"}]}}],"versions":["0.2.6","v0.2.6"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49982.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L"}]}