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.

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squashfs_opendir in unsquash-1.c in Squashfs-Tools 4.5 stores the filename in the directory entry; this is then used by unsquashfs to create the new file during the unsquash. The filename is not validated for traversal outside of the destination directory and thus allows writing to locations outside of the destination.

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The vulnerability of the `squashfs_opendir` function in the `unsquash-1.c` component of the Squashfs-Tools tooling suite relates to name space limitations on directories. This vulnerability allows an attacker to compromise data integrity and cause service failures.

The vulnerability of the squashfs-opendir function in the unsquash-1.c component of the Squashfs-Tools tooling suite relates to deficiencies in pathname limitation. Exploiting this vulnerability could allow an attacker to compromise data integrity and cause service failures...