What is CVE-2026-45851?

CVE-2026-45851 is a unscored severity Linux kernel vulnerability, 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 pending NVD analysis out of 10, rated awaiting scoring severity.

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.

CVE-2026-45851

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 2026-05-27

Patch available

Yes

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

The following references provide additional information about CVE-2026-45851 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/0862438c90487e79822d5647f854977d50381505
Patch
Kernel patch commit
https://git.kernel.org/stable/c/9b18bf59977f5c5bc3b11b210520f62500a7adf3
Patch
Kernel patch commit
https://git.kernel.org/stable/c/b7bc182ec1846be437351e44164089d988f9d0dd
Patch

5 patch commits total View all on NVD

Frequently asked questions

What is CVE-2026-45851?

CVE-2026-45851 is a unscored severity Linux kernel vulnerability . 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.
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.