Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV L L N R U H N N 5.5 .0033 25.8 —
AFFECTED Product Versions Fixed n/a n/a – —
TIMELINE Apr 6 Reserved by mitre Jul 9 EXPLOIT PUBLISHED — CVE-2026-39243. Public exploit reference added. Jul 9 Published (CNA: mitre)
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.
| Date | Event | Detail |
|---|---|---|
| April 6, 2026 | Reserved | Reserved by mitre |
| July 9, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-39243. Public exploit reference added. |
| July 9, 2026 | Published | Published (CNA: mitre) |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| n/a | n/a | — | n/a | — |
Authoritative record: CVE-2026-39243 at cve.org
Weaknesses: CWE-59
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-39243 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.