// For flags

CVE-2021-41072

squashfs-tools: possible Directory Traversal via symbolic link

Severity Score

8.1
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Una función squashfs_opendir en el archivo unsquash-2.c en Squashfs-Tools versión 4.5 permite un Salto de Directorio, una vulnerabilidad diferente a CVE-2021-40153. Un sistema de archivos squashfs que ha sido diseñado para incluir un enlace simbólico y luego contenidos bajo el mismo nombre de archivo en un sistema de archivos puede causar que unsquashfs primero cree el enlace simbólico apuntando fuera del directorio esperado, y luego la operación de escritura subsiguiente causará que el proceso unsquashfs escriba mediante el enlace simbólico en otra parte del sistema de archivos

A directory traversal flaw was found in squashfs-tools. During extraction, a file can escape the destination directory by using a symbolic link, and a regular file with an identical name. This flaw allows a specially crafted squashfs archive to install or overwrite files outside of the destination directory.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-09-14 CVE Reserved
  • 2021-09-14 CVE Published
  • 2024-07-23 EPSS Updated
  • 2024-08-04 CVE Updated
  • 2024-08-04 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-59: Improper Link Resolution Before File Access ('Link Following')
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Squashfs-tools Project
Search vendor "Squashfs-tools Project"
Squashfs-tools
Search vendor "Squashfs-tools Project" for product "Squashfs-tools"
4.5
Search vendor "Squashfs-tools Project" for product "Squashfs-tools" and version "4.5"
-
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
10.0
Search vendor "Debian" for product "Debian Linux" and version "10.0"
-
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
11.0
Search vendor "Debian" for product "Debian Linux" and version "11.0"
-
Affected