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CVE-2023-34256

Published: May 31, 2023Updated: Mar 11, 2025 Sources: CVE List NVD BDU csafCWE-125
NVD MITRE
5.5CVSSMEDIUM
EPSS Score
0.2%
Top 84.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

An issue was discovered in the Linux kernel before 6.3.3. There is an out-of-bounds read in crc16 in lib/crc16.c when called from fs/ext4/super.c because ext4_group_desc_csum does not properly check an offset. NOTE: this is disputed by third parties because the kernel is not intended to defend against attackers with the stated "When modifying the block device while it is mounted by the filesystem" access.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:UC:NI:NA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-125

Affected Products

n/an/a
linux kernellinux
On-premOS
Operating Systems
linux enterprisesuse
On-prem
Operating Systems / linux-distro
debian linuxdebian
On-premOS
Operating Systems / linux-distro
Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
linuxoss-projectOperating Systemsaka the linux kernel
susecommercialDEOperating Systems
debianoss-projectGBOperating Systemsaka debian gnu/linux
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
and 5 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://syzkaller.appspot.com/bug?extid=8785e41224a3afd04321
syzkaller.appspot.com
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4f04351888a83e595571de672e0a4a8b74f4fb31
git.kernel.org
https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.3
cdn.kernel.org
and 45 more references View all →

Timeline

Published
May 31, 2023
Last Updated
Mar 11, 2025

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