CVE-2026-39973

Apktool is a tool for reverse engineering Android APK files. In versions 3.0.0 and 3.0.1, a path traversal vulnerability in `brut/androlib/res/decoder/ResFileDecoder.java` allows a maliciously crafted APK to write arbitrary files to the filesystem during standard decoding (`apktool d`). This is a security regression introduced in commit e10a045 (PR #4041, December 12, 2025), which removed the `BrutIO.sanitizePath()` call that previously prevented path traversal in resource file output paths. An attacker can embed `../` sequences in the `resources.arsc` Type String Pool to escape the output directory and write files to arbitrary locations, including `~/.ssh/config`, `~/.bashrc`, or Windows Startup folders, escalating to RCE. The fix in version 3.0.2 re-introduces `BrutIO.sanitizePath()` in `ResFileDecoder.java` before file write operations.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/iBotPeaches/Apktool/commit/e10a0450c7afcd9462c0b76bcbff0e7428b92bdd#diff-cd531ebe1014bfd18185bf21585ca5cdb16fbcb07703ebc47949a1b4e4e36bc3	Patch
https://github.com/iBotPeaches/Apktool/pull/4041	Issue Tracking
https://github.com/iBotPeaches/Apktool/releases/tag/v3.0.2	Product
https://github.com/iBotPeaches/Apktool/security/advisories/GHSA-m8mh-x359-vm8m	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apktool:apktool:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-21 02:16

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39973

Mitre link : CVE-2026-39973

CVE.ORG link : CVE-2026-39973

JSON object : View

Products Affected

apktool

apktool

CWE

CWE-22

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

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