CVE-2026-86071

LowCVSS 3.7

Published: 16/09/2026(UTC)Updated: 24/09/2026(UTC)Translated: 17/09/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.36%

27th percentile - higher than 27% of all known CVEs

Summary

Junrar is an open source Java RAR archive library. Prior to version 7.6.1, LocalFolderExtractor can create directories outside the intended extraction root when processing a crafted archive entry, because createFile() validates only the final canonical file path while makeFile() creates intermediate path segments with unchecked mkdir() calls. This can enable filesystem pollution or file-versus-directory squatting that can make later security-sensitive writes fail.

Risk Assessment

This can lead to filesystem pollution or cause later security-sensitive writes to fail; the demonstrated impact is directory creation, not unconditional arbitrary file-content write.

Recommendation

Upgrade the Junrar library to version 7.6.1, which fixes this issue.

Other vulnerabilities in Junrar

CVE-2026-41245Medium
In the Junrar library prior to version 7.5.10, a path traversal vulnerability in the `LocalFolderExtractor` class allows an attacker to write arbitrary files with attacker-controlled content into sibling directories when extracting a crafted RAR archive.

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS