Path Traversal in Squashfs-Tools Project

CVE-2021-40153

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.

Vulnerability class: Path Traversal (Directory Traversal)

EPSS: 0.025 (83.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-40153?
CVE-2021-40153 is a high-severity vulnerability in Squashfs-Tools Project, classified under Path Traversal. CVSS score: 8.1/10. Published 2021-08-27.
How severe is CVE-2021-40153?
High severity. CVSS v3 base score is 8.1 out of 10.
Is CVE-2021-40153 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.