CVE-2026-85396

rubyzip versions before 3.4.0 contain a path traversal vulnerability in Zip::Entry#extract that fails to properly validate extraction paths using prefix comparison without trailing separators. Attackers can craft archive entries with names like ../upload_backup/owned.sh to write files outside the intended extraction directory into sibling paths sharing the destination prefix.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/geo-chen/oss/blob/main/rubyzip.md
https://github.com/rubyzip/rubyzip
https://github.com/rubyzip/rubyzip/blob/v3.3.1/lib/zip/entry.rb
https://github.com/rubyzip/rubyzip/commit/17edfbf4423b83211b075acc23a7d8640da63449
https://github.com/rubyzip/rubyzip/releases/tag/v3.4.0
https://www.vulncheck.com/advisories/rubyzip-before-3.4.0-path-traversal-in-zip-entry-extract-via-sibling-directory-prefix

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-03 19:17

Updated : 2026-09-03 19:17

NVD link : CVE-2026-85396

Mitre link : CVE-2026-85396

CVE.ORG link : CVE-2026-85396

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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