CVE-2026-93045
bpf: Reject arena frees below the arena base
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject arena frees below the arena base bpf_arena_free_pages() accepts scalar arena addresses. The runtime masks the address to the low 32 bits and reconstructs a full user address from the arena base before returning the range to the arena free tree. When the scalar value is below the low 32 bits of the arena base, full_uaddr falls below user_vm_start. The existing upper-end clipping then turns this into an out-of-range free-tree offset. A later allocation can reuse that offset and return an address below the arena mapping. Reject such frees before computing the clipped range.
INFO
Published Date :
Sept. 17, 2026, 5:17 p.m.
Last Modified :
Sept. 18, 2026, 6:18 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to the latest stable version.
- Verify the patch addresses the bpf_arena_free_pages issue.
- Reboot systems after kernel updates are applied.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-93045.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-93045 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-93045
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-93045 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-93045 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 18, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 17, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: bpf: Reject arena frees below the arena base bpf_arena_free_pages() accepts scalar arena addresses. The runtime masks the address to the low 32 bits and reconstructs a full user address from the arena base before returning the range to the arena free tree. When the scalar value is below the low 32 bits of the arena base, full_uaddr falls below user_vm_start. The existing upper-end clipping then turns this into an out-of-range free-tree offset. A later allocation can reuse that offset and return an address below the arena mapping. Reject such frees before computing the clipped range. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/93xxx/CVE-2026-93045.json">CVE-2026-93045</a> Added Reference https://git.kernel.org/stable/c/8a08635656037aee9c12231ed384449c4ffb1a93 Added Reference https://git.kernel.org/stable/c/90453eaf8f14e7be0ab03983f2a93aeb6b990a58 Added Reference https://git.kernel.org/stable/c/a968dffa5ab3c74d2ebb3a6233bf8b843f0bfc20 Added Reference https://git.kernel.org/stable/c/b5a71cb2db6d84ac0042549dcec266b18429d41e