CVE-2026-86071Junrar: LocalFolderExtractor mkdir escape allows directory creation outside extraction root
- 3.7LowCVSS base score
- 0.36%Exploitation in 30 daysEPSS · top 69% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Junrar is an open source Java RAR archive library. Prior to version 7.6.1, LocalFolderExtractor in src/main/java/com/github/junrar/LocalFolderExtractor.java can create directories outside the intended extraction root when processing a crafted archive entry. LocalFolderExtractor.createFile() validates only the final canonical file path, while LocalFolderExtractor.makeFile() creates intermediate path segments with unchecked mkdir() calls. An entry can therefore make the final path resolve inside the destination while causing intermediate directory creation outside it, enabling filesystem pollution or file-versus-directory squatting that can make later security-sensitive writes fail. The demonstrated impact is directory creation, not unconditional arbitrary file-content write. This issue is fixed in version 7.6.1.
Timeline
ID reserved
By GitHub_M
- 12 days later
· 12 days later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Low3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Low3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.36% · top 69% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.7.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavencom.github.junrar:junrarGHSA-89m4-43j5-vhhx (opens in a new tab)
References
References3
- https://github.com/junrar/junrar/security/advisories/GHSA-89m4-43j5-vhhx (opens in a new tab)x_refsource_CONFIRM
- https://github.com/junrar/junrar/commit/e6e333b195a1e3ad271a18fd79d8ac1eb5289343 (opens in a new tab)x_refsource_MISC
- https://github.com/junrar/junrar/releases/tag/v7.6.1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-81011 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-89m4-43j5-vhhx (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-86071)Record last updated .