What is CVE-2026-45851?

CVE-2026-45851 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 6.6 onward and patched in 6.6.128, 6.12.75, 6.18.14 and others. CVE-2026-45851 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-45851?

CVE-2026-45851 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-2026-45851?

Yes, CVE-2026-45851 has been patched. Fixed versions include 6.6.128, 6.12.75, 6.18.14 and others. If you are running Linux kernel 6.6 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-45851 actively exploited?

CVE-2026-45851 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-2026-45851

High

In the Linux kernel, the following vulnerability has been resolved: efi: Fix reservation of unaccepted memory table The reserve_unaccepted() function incorrectly calculates the size of the memblock reservation for the unaccepted memory table. It aligns the size of the table, but fails to account for cases where the table's starting physical address (efi.unaccepted) is not page-aligned. If the table starts at an offset within a page and its end crosses into a subsequent page that the aligned size does not cover, the end of the table will not be reserved. This can lead to the table being overwritten or inaccessible, causing a kernel panic in accept_memory(). This issue was observed when starting Intel TDX VMs with specific memory sizes (e.g., > 64GB). Fix this by calculating the end address first (including the unaligned start) and then aligning it up, ensuring the entire range is covered by the reservation.

Package Linux Kernel

Published 2026-05-27

Last modified 2026-06-25

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-2026-45851 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 6.6 and later are affected. Fixed in 6.6.128, 6.12.75, 6.18.14, 6.19.4, 7.0 and their respective stable series.

Affected from

≥ 6.6

Fixed in

✓ 6.6.128 6.6.x ✓ 6.12.75 6.12.x ✓ 6.18.14 6.18.x ✓ 6.19.4 6.19.x ✓ 7.0

References

5 total

Kernel Git
https://git.kernel.org/stable/c/0862438c90487e79822d5647f854977d50381505

Patch
Kernel Git
https://git.kernel.org/stable/c/9b18bf59977f5c5bc3b11b210520f62500a7adf3

Patch
Kernel Git
https://git.kernel.org/stable/c/b7bc182ec1846be437351e44164089d988f9d0dd

Patch
Kernel Git
https://git.kernel.org/stable/c/ba6b6f1502fa55621d1db23f253d54322bdbe4e0

Patch
Kernel Git
https://git.kernel.org/stable/c/e649b5916725c68f44ebf45fb396df563c5dbaf2

Patch

Details

CVE ID CVE-2026-45851

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2026-05-27

Modified 2026-06-25

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-45851?

CVE-2026-45851 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 6.6 onward and has been patched in 6.6.128, 6.12.75, 6.18.14 and others. CVE-2026-45851 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-45851?

CVE-2026-45851 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-2026-45851?

Yes. CVE-2026-45851 has been patched. Fixed versions include 6.6.128, 6.12.75, 6.18.14 and others. If you are running Linux kernel 6.6 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-45851 actively exploited?

No. CVE-2026-45851 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.