What is CVE-2026-53303?

CVE-2026-53303 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10, classified as a Out-of-bounds Read flaw (CWE-125), affecting Linux kernel versions from 4.17 onward and patched in 6.1.175, 6.6.141, 6.12.91 and others. CVE-2026-53303 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-53303?

CVE-2026-53303 has a CVSS score of 7.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.

Is there a patch available for CVE-2026-53303?

Yes, CVE-2026-53303 has been patched. Fixed versions include 6.1.175, 6.6.141, 6.12.91 and others. If you are running Linux kernel 4.17 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-53303 actively exploited?

CVE-2026-53303 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Out-of-bounds Read (CWE-125)?

The product reads data past the end or before the beginning of the intended buffer. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/125.html

CVE-2026-53303

High

In the Linux kernel, the following vulnerability has been resolved: f2fs: protect extension_list reading with sb_lock in f2fs_sbi_show() In f2fs_sbi_show(), the extension_list, extension_count and hot_ext_count are read without holding sbi->sb_lock. If a concurrent sysfs store modifies the extension list via f2fs_update_extension_list(), the show path may read inconsistent count and array contents, potentially leading to out-of-bounds access or displaying stale data. Fix this by holding sb_lock around the entire extension list read and format operation.

Package Linux Kernel

Published 2026-06-26

Last modified 2026-07-06

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.1

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-125

CVE-2026-53303 is a Out-of-bounds Read vulnerability

What is Out-of-bounds Read?

The product reads data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

Affected versions

Linux kernel versions 4.17 and later are affected. Fixed in 6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10, 7.1 and their respective stable series.

Affected from

≥ 4.17

Fixed in

✓ 6.1.175 6.1.x ✓ 6.6.141 6.6.x ✓ 6.12.91 6.12.x ✓ 6.18.33 6.18.x ✓ 7.0.10 7.0.x ✓ 7.1

References

6 total

Kernel Git
https://git.kernel.org/stable/c/4b3a1bf4c2ffd4c9595d900ead78c9035894a025

Patch
Kernel Git
https://git.kernel.org/stable/c/5909bedbed38c558bee7cb6758ceedf9bc3a9194

Patch
Kernel Git
https://git.kernel.org/stable/c/cea15f66b7b68b2c50943a6660e0692c6635e4eb

Patch
Kernel Git
https://git.kernel.org/stable/c/d0e877810baf613b018fd9747440b9d4d9db1428

Patch
Kernel Git
https://git.kernel.org/stable/c/d3ff0c121bbaef026df6248ab7ef6f0b068b0647

Patch

Showing 5 of 6 references View all on NVD

Details

CVE ID CVE-2026-53303

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2026-06-26

Modified 2026-07-06

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-53303?

CVE-2026-53303 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 , classified as an Out-of-bounds Read flaw (CWE-125) . It affects Linux kernel versions from 4.17 onward and has been patched in 6.1.175, 6.6.141, 6.12.91 and others. CVE-2026-53303 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-53303?

CVE-2026-53303 has a CVSS score of 7.1 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.
Is there a patch available for CVE-2026-53303?

Yes. CVE-2026-53303 has been patched. Fixed versions include 6.1.175, 6.6.141, 6.12.91 and others. If you are running Linux kernel 4.17 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-53303 actively exploited?

No. CVE-2026-53303 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.