CVE-2026-45390

Deferred Deferred - Pending Action

Directory Traversal Vulnerability in OCaml-tar

Publication date: 2026-06-15

Last updated on: 2026-06-16

Assigner: MITRE

Description

In OCaml-tar before 3.4.0, a crafted archive with ../ path segments in its name allows escaping the current working directory. This is not desired behavior, and tar(1) rejects such extractions, but ocaml-tar decompresses it anyway. The impact is that it allows arbitrary file writes outside of the desired extraction directory (to an attacker that can reach a tar decompression endpoint).

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-06-15

Last Modified

2026-06-16

Generated

2026-07-06

AI Q&A

2026-06-15

EPSS Evaluated

2026-07-04

NVD

CVE-2026-45390

EUVD

EUVD-2026-36766

Affected Vendors & Products

Vendor	Product	Version / Range
ocaml	ocaml-tar	to 3.4.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-22	The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

Attack-Flow Graph

Executive Summary

In OCaml-tar versions before 3.4.0, there is a vulnerability where a specially crafted archive containing '../' path segments in file names can escape the intended extraction directory.

While the standard tar utility (tar(1)) rejects such extractions to prevent directory traversal, ocaml-tar decompresses these archives anyway, allowing files to be written outside the target directory.

Impact Analysis

This vulnerability allows an attacker who can provide a tar archive to a decompression endpoint using ocaml-tar to write arbitrary files outside the intended extraction directory.

This can lead to overwriting critical files, potentially resulting in unauthorized code execution, data corruption, or system compromise.

Compliance Impact

This vulnerability allows arbitrary file writes outside of the intended extraction directory, which can lead to unauthorized modification or overwriting of files on the system.

Such unauthorized file writes can compromise data integrity and confidentiality, potentially violating requirements in standards and regulations like GDPR and HIPAA that mandate protection of sensitive data and secure handling of information.

Therefore, if exploited, this vulnerability could negatively impact compliance with these regulations by enabling attackers to alter or place files in unauthorized locations.

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