Debian Security Advisory

DLA-2752-1 squashfs-tools -- LTS security update

Date Reported:
31 Aug 2021
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2021-40153.
More information:

An issue has been found in squashfs-tools, a tool to create and append to squashfs filesystems. As unsquashfs did not validate all filepaths, it would allow writing outside of the original destination.

For Debian 9 stretch, this problem has been fixed in version 1:4.3-3+deb9u2.

We recommend that you upgrade your squashfs-tools packages.

For the detailed security status of squashfs-tools please refer to its security tracker page at:

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: