(0Day) BusyBox libarchive Symlink Directory Traversal Arbitrary File Creation Vulnerability
Vulnerability Details
This vulnerability allows remote attackers to create arbitrary files on affected installations of BusyBox. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the libarchive component. The issue results from the lack of proper validation of a user-supplied path prior to using it in file operations. An attacker can leverage this vulnerability to create files in the context of the current user.
Additional Details
10/03/25 – ZDI reported the vulnerability to the vendor
10/10/25 – ZDI followed up asking the vendor to confirm receipt of the report
12/10/25 – ZDI asked for updates
04/09/26 – ZDI notified the vendor of the intention to publish the case as 0-day advisory
-- Mitigation: Given the nature of the vulnerability, the only salient mitigation strategy is to restrict interaction with the product
Disclosure Timeline
- 2025-10-03 - Vulnerability reported to vendor
- 2026-09-16 - Coordinated public release of advisory
- 2026-09-16 - Advisory Updated
Credit
Ryota Shiga (GMO Flatt Security Inc.) with takumi-san.ai
