CVE-2023-53450 [Medium] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: ext4: remove a BUG_ON in ext4_mb_release_group_pa() If a malicious fuzzer overwrites the ext4 superblock while it is mounted such that the s_first_data_block is set to a very large number, the calculation of the block group can underflow, and trigger a BUG_ON check. Change this to be an ext4_warning so that we don't crash the kernel.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.03%	0.15%	+0.11%
2	2025-10-01	—	0.03%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.03%

0.15%

+0.11%

2025-10-01

—

0.03%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

3.6

[email protected]

OS Trackers for CVE-2023-53450

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2023-53450 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2023-53450
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2023-53450
`suse`	medium	CVE-2023-53450 severity moderate: SUSE including 25 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 107 product×package rows across 23 product lines (SUSE Linux Enterprise High Availability Extension 15 SP7, SUSE Linux Enterprise Live Patching 12 SP5, … (23 product lines)): Known Not Affected 88, Will Not Fix 19.	https://www.suse.com/security/cve/CVE-2023-53450/
`ubuntu`	medium	CVE-2023-53450 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 162, released 138, not-affected 76, needed 20, needs-triage 1.	https://ubuntu.com/security/CVE-2023-53450

Affected software / configurations for CVE-2023-53450

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 2.6.25, < 4.14.315	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.15, < 4.19.283	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.20, < 5.4.243	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.5, < 5.10.180	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.112	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.29	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.2.16	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.3, < 6.3.3	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.4	cpe:2.3:o:linux:linux_kernel:6.4:rc1::::::

References for CVE-2023-53450

URL	Tags
https://git.kernel.org/stable/c/185062a21976fbc38f2efd296951b02c4500cf65	Patch
https://git.kernel.org/stable/c/463808f237cf73e98a1a45ff7460c2406a150a0b	Patch
https://git.kernel.org/stable/c/53c14e7cc2257191ba15425c15638fc4f8abb92b	Patch
https://git.kernel.org/stable/c/978e5e9111af18741449b81fefd531a622dd969a	Patch
https://git.kernel.org/stable/c/b0fc279de4bf17e1710bb7e83906538ff8f11111	Patch
https://git.kernel.org/stable/c/bf2a16eb4e6d06124bd8436d4546f61539a65f29	Patch
https://git.kernel.org/stable/c/d5bf8f7fb3ee3d99d1303ceb54599ea0599a4a5b	Patch
https://git.kernel.org/stable/c/d87a4e4094c9879fc8acdff8ce59fdffa979c8e0	Patch
https://git.kernel.org/stable/c/ef16d8a1798db1a1604ac44ca1bd73ec6bebf483	Patch

URL

CVE-2023-53450 | ext4: remove a BUG_ON in ext4_mb_release_group_pa()

Exploit prediction scoring system (EPSS) score for CVE-2023-53450

Common vulnerability scoring system (CVSS) metrics for CVE-2023-53450

Weakness enumeration for CVE-2023-53450

OS Trackers for CVE-2023-53450

Affected software / configurations for CVE-2023-53450

References for CVE-2023-53450