SB2019102234 - Path traversal in pacman (Alpine package)
Published: October 22, 2019
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Path traversal (CVE-ID: CVE-2019-9686)
CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
pacman before 5.1.3 allows directory traversal when installing a remote package via a specified URL "pacman -U <url>" due to an unsanitized file name received from a Content-Disposition header. pacman renames the downloaded package file to match the name given in this header. However, pacman did not sanitize this name, which may contain slashes, before calling rename(). A malicious server (or a network MitM if downloading over HTTP) can send a Content-Disposition header to make pacman place the file anywhere in the filesystem, potentially leading to arbitrary root code execution. Notably, this bypasses pacman's package signature checking. This occurs in curl_download_internal in lib/libalpm/dload.c.
Remediation
Install update from vendor's website.