Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 6.6.1, < 6.6.128 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/0862438c90487e79822d5647f854977d50381505Patch
- https://git.kernel.org/stable/c/9b18bf59977f5c5bc3b11b210520f62500a7adf3Patch
- https://git.kernel.org/stable/c/b7bc182ec1846be437351e44164089d988f9d0ddPatch
- https://git.kernel.org/stable/c/ba6b6f1502fa55621d1db23f253d54322bdbe4e0Patch
- https://git.kernel.org/stable/c/e649b5916725c68f44ebf45fb396df563c5dbaf2Patch
FAQ
What is CVE-2026-45851?
CVE-2026-45851 is a vulnerability with a CVSS score of 7.1 (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 ...
How severe is CVE-2026-45851?
CVE-2026-45851 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-45851?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.