{"id":"CVE-2026-39973","summary":"Apktool: Path Traversal to Arbitrary File Write","details":"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.","aliases":["GHSA-m8mh-x359-vm8m"],"modified":"2026-07-15T01:49:10.377735176Z","published":"2026-04-21T01:35:22.396Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39973.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-22"]},"references":[{"type":"WEB","url":"https://github.com/iBotPeaches/Apktool/releases/tag/v3.0.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39973.json"},{"type":"ADVISORY","url":"https://github.com/iBotPeaches/Apktool/security/advisories/GHSA-m8mh-x359-vm8m"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39973"},{"type":"FIX","url":"https://github.com/iBotPeaches/Apktool/commit/e10a0450c7afcd9462c0b76bcbff0e7428b92bdd#diff-cd531ebe1014bfd18185bf21585ca5cdb16fbcb07703ebc47949a1b4e4e36bc3"},{"type":"FIX","url":"https://github.com/iBotPeaches/Apktool/pull/4041"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/ibotpeaches/apktool","events":[{"introduced":"f770b39e425af4fa6ac4ca1e9ea6c4824339c6d3"},{"fixed":"1c1d15b070c2138d958fa8b685d430c49c4bb117"},{"fixed":"e10a0450c7afcd9462c0b76bcbff0e7428b92bdd"}],"database_specific":{"cpe":"cpe:2.3:a:apktool:apktool:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"3.0.0"},{"fixed":"3.0.2"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v3.0.1","v3.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39973.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N"}]}