CVE-2021-3996
Linux Util-Linux FUSE Unmount Privilege Escalation Vulnerability
Description
A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.
INFO
Published Date :
Aug. 23, 2022, 8:15 p.m.
Last Modified :
Jan. 7, 2024, 9:15 a.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
3.6
Exploitability Score :
1.8
Public PoC/Exploit Available at Github
CVE-2021-3996 has a 1 public PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-3996.
| URL | Resource |
|---|---|
| http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html | Third Party Advisory |
| http://seclists.org/fulldisclosure/2022/Dec/4 | Mailing List Third Party Advisory |
| http://www.openwall.com/lists/oss-security/2022/11/30/2 | Mailing List Third Party Advisory |
| https://access.redhat.com/security/cve/CVE-2021-3996 | Issue Tracking Third Party Advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=2024628 | Issue Tracking Patch Third Party Advisory |
| https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb | Patch Third Party Advisory |
| https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes | Release Notes Vendor Advisory |
| https://security.gentoo.org/glsa/202401-08 | |
| https://security.netapp.com/advisory/ntap-20221209-0002/ | Broken Link Third Party Advisory |
| https://www.openwall.com/lists/oss-security/2022/01/24/2 | Exploit Mailing List Patch Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
HCL Smarty
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-3996 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-3996 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Jan. 07, 2024
Action Type Old Value New Value Added Reference Red Hat, Inc. https://security.gentoo.org/glsa/202401-08 [No types assigned] -
Modified Analysis by [email protected]
Jan. 26, 2023
Action Type Old Value New Value Changed Reference Type http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html No Types Assigned http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html Third Party Advisory Changed Reference Type http://seclists.org/fulldisclosure/2022/Dec/4 No Types Assigned http://seclists.org/fulldisclosure/2022/Dec/4 Mailing List, Third Party Advisory Changed Reference Type http://www.openwall.com/lists/oss-security/2022/11/30/2 No Types Assigned http://www.openwall.com/lists/oss-security/2022/11/30/2 Mailing List, Third Party Advisory Changed Reference Type https://security.netapp.com/advisory/ntap-20221209-0002/ No Types Assigned https://security.netapp.com/advisory/ntap-20221209-0002/ Broken Link, Third Party Advisory -
CVE Modified by [email protected]
Dec. 09, 2022
Action Type Old Value New Value Added Reference https://security.netapp.com/advisory/ntap-20221209-0002/ [No Types Assigned] -
CVE Modified by [email protected]
Dec. 09, 2022
Action Type Old Value New Value Added Reference http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html [No Types Assigned] -
CVE Modified by [email protected]
Dec. 09, 2022
Action Type Old Value New Value Added Reference http://seclists.org/fulldisclosure/2022/Dec/4 [No Types Assigned] -
CVE Modified by [email protected]
Dec. 01, 2022
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2022/11/30/2 [No Types Assigned] -
Reanalysis by [email protected]
Nov. 14, 2022
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:* versions up to (excluding) 2.37.3 OR *cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:* versions from (including) 2.34 up to (excluding) 2.37.3 -
Initial Analysis by [email protected]
Aug. 29, 2022
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://access.redhat.com/security/cve/CVE-2021-3996 No Types Assigned https://access.redhat.com/security/cve/CVE-2021-3996 Issue Tracking, Third Party Advisory Changed Reference Type https://bugzilla.redhat.com/show_bug.cgi?id=2024628 No Types Assigned https://bugzilla.redhat.com/show_bug.cgi?id=2024628 Issue Tracking, Patch, Third Party Advisory Changed Reference Type https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb No Types Assigned https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb Patch, Third Party Advisory Changed Reference Type https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes No Types Assigned https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes Release Notes, Vendor Advisory Changed Reference Type https://www.openwall.com/lists/oss-security/2022/01/24/2 No Types Assigned https://www.openwall.com/lists/oss-security/2022/01/24/2 Exploit, Mailing List, Patch, Third Party Advisory Added CWE NIST CWE-552 Added CPE Configuration OR *cpe:2.3:a:kernel:util-linux:*:*:*:*:*:*:*:* versions up to (excluding) 2.37.3 Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-3996 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-3996
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.04 }} 0.00%
score
0.05635
percentile