High severity · published Sep 11, 2026
CVE-2026-89500
ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page
7.8
CVSS
0.2%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page Discarding a cached reader page after a concurrent ring buffer resize uses the new global subbuf_order for the free_pages() call. This mismatched order may crashes the kernel or leaks memory because the cached page was allocated under the old size. Save the actual free_page order alongside the page address to ensure we always refer to the correct value and do not rely on the potentially stalled cpu_buffer->subbuf_order value. The simplest is to make free_page a buffer_data_read_page which already covers exactly what we need: a page address and a page order.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
8e7b58c27b3c567316a51079b375b846f9223bba before d8f52dc3c3f1f987d8cf920ccd8d66590870bf3f; 8e7b58c27b3c567316a51079b375b846f9223bba before a1dabe68fb53730bc0be60c5dbfd3f4c560084e7; 8e7b58c27b3c567316a51079b375b846f9223bba before d787d509bdf6c88c85e095247daf7456cb7fb772; 8e7b58c27b3c567316a51079b375b846f9223bba before 7a1fb95de5404134f8758c1295ce88986bdf117c; 6.8 · source: vendor