CVE-2021-40153

Public Exploit

Description

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.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.44%
Vendor Advisory fedoraproject.org Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/plougher/squashfs-tools/commit/79b5a555058eef4e1e7ff220c344d39f8cd09646 third party advisory patch
https://github.com/plougher/squashfs-tools/issues/72 third party advisory exploit
https://bugs.launchpad.net/ubuntu/+source/squashfs-tools/+bug/1941790 third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RAOZ4BKWAC4Y3U2K5MMW3S77HWWXHQDL/ vendor advisory
https://lists.debian.org/debian-lts-announce/2021/08/msg00030.html third party advisory mailing list
https://www.debian.org/security/2021/dsa-4967 third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GSMRKVJMJFX3MB7D3PXJSYY3TLZROE5S/ vendor advisory
https://security.gentoo.org/glsa/202305-29 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-40153?
CVE-2021-40153 has been scored as a high severity vulnerability.
How to fix CVE-2021-40153?
To fix CVE-2021-40153, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-40153 being actively exploited in the wild?
It is possible that CVE-2021-40153 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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