Description
squashfs_opendir in unsquash-2.c in Squashfs-Tools 4.5 allows Directory Traversal, a different vulnerability than CVE-2021-40153. A squashfs filesystem that has been crafted to include a symbolic link and then contents under the same filename in a filesystem can cause unsquashfs to first create the symbolic link pointing outside the expected directory, and then the subsequent write operation will cause the unsquashfs process to write through the symbolic link elsewhere in the filesystem.
References (5)
Core 5
Core References
Third Party Advisory vendor-advisory
https://www.debian.org/security/2021/dsa-4987
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2021/10/msg00017.html
Third Party Advisory vendor-advisory
https://security.gentoo.org/glsa/202305-29
Patch, Third Party Advisory
https://github.com/plougher/squashfs-tools/commit/e0485802ec72996c20026da320650d8362f555bd
Exploit, Third Party Advisory
https://github.com/plougher/squashfs-tools/issues/72#issuecomment-913833405
Scores
CVSS v3
8.1
EPSS
0.0214
EPSS Percentile
79.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
Details
CWE
CWE-22
CWE-59
Status
published
Products (4)
debian/debian_linux
9.0
debian/debian_linux
10.0
debian/debian_linux
11.0
squashfs-tools_project/squashfs-tools
4.5
Published
Sep 14, 2021
Tracked Since
Feb 18, 2026