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CVE-2021-3492

Ubuntu linux kernel shiftfs file system double free vulnerability

Published: Apr 17, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-401
NVD MITRE
8.8CVSSHIGH
EPSS Score
1.5%
Top 28.2%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available

Description

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:CC:HI:HA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-401CWE-415

Affected Products

Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Linux kernelUbuntu
On-prem
Operating Systems / linux-distro
ubuntu linuxcanonical
On-premOS
Operating Systems / linux-distro
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
ubuntucommercialGBOperating Systemsaka ubuntu linux
canonicalcommercialGBOperating Systemsaka canonical ltd.

Attack Graph

Products CVE Techniques Tactics

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Exploitability

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Privilege Escalation
View detailed technique mapping

References

https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333
git.launchpad.net
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6
git.launchpad.net
https://github.com/synacktiv/CVE-2021-3492
github.com
and 10 more references View all →

Timeline

Published
Apr 17, 2021
Last Updated
Nov 21, 2024

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