CVE-2026-45851

HIGH
MEDIUM Priority: 0.01 BB Relevance: 39/100
Published: 2026-05-27 Modified: 2026-11-06 First seen: 2026-11-06 Status: active

Attack Surface

Low Complexity No Interaction Conf. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: High
I: None
A: High

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.

Weakness Classification (1)

Affected Software (13)

VendorProductVersion
Linux Linux 8dbe33956d96c9d066ef15ca933ede30748198b2 < b7bc182ec1846be437351e44164089d988f9d0dd
Linux Linux 8dbe33956d96c9d066ef15ca933ede30748198b2 < ba6b6f1502fa55621d1db23f253d54322bdbe4e0
Linux Linux 8dbe33956d96c9d066ef15ca933ede30748198b2 < 9b18bf59977f5c5bc3b11b210520f62500a7adf3
Linux Linux 8dbe33956d96c9d066ef15ca933ede30748198b2 < e649b5916725c68f44ebf45fb396df563c5dbaf2
Linux Linux 8dbe33956d96c9d066ef15ca933ede30748198b2 < 0862438c90487e79822d5647f854977d50381505
Linux Linux 6.6
linux linux_kernel 6.6.1 – 6.6.128
linux linux_kernel 6.6
linux linux_kernel 6.6
linux linux_kernel 6.6
linux linux_kernel 6.6
linux linux_kernel 6.6
linux linux_kernel 6.6

Bug Bounty Relevance

39 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.1 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS — Exploitation Probability

0.16%
Raw Score 0.001640
Percentile 5.7%
Date 2026-11-06

Intelligence Sources

mitre ref →
nvd ref →