CVE-2026-46486: MVT Path Traversal Vulnerability

CVE-2026-46486 Overview

CVE-2026-46486 is a path traversal vulnerability [CWE-22] in the Mobile Verification Toolkit (MVT), an open source forensics tool used by investigators to identify signs of compromise on mobile devices. The flaw exists in the iOS Backup processing logic, where File identifiers are consumed without sanitization. An attacker who supplies a crafted iOS backup to an analyst can cause MVT to write or read files outside the intended extraction directory. The issue affects MVT versions prior to 2026.5.12 and was fixed in release 2026.5.12.

Critical Impact
A malicious iOS backup processed by MVT can trigger path traversal, allowing files to be placed or accessed outside the forensic working directory on the analyst's workstation.

Affected Products

Mobile Verification Toolkit (MVT) prior to version 2026.5.12
MVT iOS Backup processing module
Forensic workstations running vulnerable MVT releases

Discovery Timeline

2026-06-08 - CVE-2026-46486 published to NVD
2026-06-09 - Last updated in NVD database

Technical Details for CVE-2026-46486

Vulnerability Analysis

The vulnerability resides in MVT's iOS Backup processing pipeline. iOS backups contain a Manifest.db (or Manifest.mbdb) that maps each backed-up file to a hashed File identifier, along with its original domain and relativePath. MVT uses these identifiers when reconstructing the file layout during forensic analysis.

Prior to version 2026.5.12, MVT did not sanitize these File identifiers before joining them to the on-disk extraction path. An attacker who controls the contents of an iOS backup can embed traversal sequences such as ../ within identifiers or path fields. When MVT processes the backup, the resulting file operations resolve outside the intended output directory.

Exploitation requires user interaction: an analyst must run MVT against the attacker-supplied backup. Because MVT typically runs with the privileges of the investigator, traversal can target sensitive locations writable by that user, including configuration files, SSH keys, or scripts in the analyst's home directory.

Root Cause

The root cause is missing input validation on File identifiers and path components extracted from an untrusted iOS backup manifest. MVT concatenated these values into output paths without verifying that the resolved path remained within the designated extraction root, violating standard guidance for [CWE-22] path traversal prevention.

Attack Vector

The attack vector is network-adjacent in the sense that the malicious backup can be delivered remotely (email, shared storage, evidence transfer), but the trigger is local processing by MVT. The attacker crafts a backup whose manifest entries contain traversal sequences, then induces an analyst to run MVT commands such as mvt-ios check-backup against it. Successful exploitation results in arbitrary file writes or reads within the privileges of the user executing MVT.

No verified public proof-of-concept code is currently available. Technical specifics are documented in the GitHub Security Advisory GHSA-5h3g-px23-w6vw.

Detection Methods for CVE-2026-46486

Indicators of Compromise

Files created by MVT outside the configured output directory, particularly in the analyst's home directory or system paths.
iOS backup manifests containing .., absolute paths, or unusual characters in File identifier or relativePath fields.
Unexpected modifications to dotfiles such as .bashrc, .zshrc, or ~/.ssh/authorized_keys following an MVT run.

Detection Strategies

Inspect MVT output logs for file write paths that resolve outside the --output directory passed on the command line.
Pre-validate iOS backup manifests with a script that flags entries containing path traversal sequences before running MVT.
Run MVT inside a container or sandboxed user account so that any out-of-bounds writes are visible against an isolated filesystem baseline.

Monitoring Recommendations

Enable filesystem auditing on forensic workstations to record file creations performed by the MVT process and its Python interpreter.
Track the installed MVT version across analyst workstations and alert when releases earlier than 2026.5.12 are detected.
Centralize MVT execution logs in a SIEM or data lake to correlate backup ingestion events with subsequent file activity.

How to Mitigate CVE-2026-46486

Immediate Actions Required

Upgrade MVT to version 2026.5.12 or later on every forensic workstation and analysis pipeline.
Re-process any iOS backups that were analyzed with vulnerable MVT versions and originated from untrusted sources.
Review analyst home directories and MVT working directories for files created outside the expected extraction path.

Patch Information

The vulnerability is fixed in MVT release 2026.5.12, which adds sanitization of File identifiers during iOS Backup processing. Release notes and source changes are available in the GitHub Release v2026.5.12. Coordinated disclosure details are documented in the GitHub Security Advisory GHSA-5h3g-px23-w6vw.

Workarounds

Process untrusted iOS backups only inside disposable virtual machines or containers with no access to sensitive host paths.
Run MVT as a dedicated low-privilege user account that has write access only to a dedicated forensic output directory.
Validate iOS backup manifests for traversal sequences before invoking MVT if upgrading to 2026.5.12 is not immediately possible.

bash

# Configuration example: upgrade MVT and run under an isolated account
pip install --upgrade 'mvt>=2026.5.12'
mvt --version

# Run MVT as a dedicated user with a scoped output directory
sudo -u mvt-analyst mvt-ios check-backup \
  --output /srv/mvt/output/case-001 \
  /srv/mvt/evidence/case-001/backup