{"cve":"CVE-2026-39243","nvd":{"published":"2026-07-09T22:17:04.113","modified":"2026-07-13T12:57:34.913","status":"Analyzed","description":"decompress before 4.2.2 allows arbitrary hardlink creation during archive extraction, enabling file read disclosure and file corruption. When processing hardlink entries (type === 'link'), the x.linkname field from the archive is passed directly to fs.link() without validation (index.js line 113). An attacker can craft an archive with a hardlink entry whose linkname is an absolute path to any file on the same filesystem. This creates a hardlink inside the extraction directory that shares the same inode as the target file, enabling both reading and overwriting the original file's content. Hardlinks are limited to files on the same filesystem and cannot target directories.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","score":5.5},"cwes":["CWE-59"],"references":["https://github.com/kevva/decompress","https://github.com/kevva/decompress/issues/113","https://www.npmjs.com/package/decompress","https://github.com/kevva/decompress/issues/113"],"products":["decompress_project:decompress"],"source":"nvd","synced_at":"2026-10-19T22:44:02.134301115+00:00"},"epss":{"cve":"CVE-2026-39243","score":0.00301,"percentile":0.22907,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-jwp9-9v96-94mx","url":"https://osv.dev/vulnerability/GHSA-jwp9-9v96-94mx","summary":"decompress allows arbitrary hardlink creation during archive extraction","modified":"2026-08-13T14:41:01.067573Z","packages":[{"ecosystem":"npm","name":"decompress","purl":"pkg:npm/decompress","ranges":["<=4.2.1"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}