CVE-2026-93045

bpf: Reject arena frees below the arena base

HIGH
7.8
CVSS Score
Published: September 17, 2026 at 04:10 PM UTC
Updated: October 19, 2026 at 10:16 AM UTC
1 product affected across 1 vendorLinux Kernel

Using Linux by Linux?

Get instant alerts when new vulnerabilities affect Linux - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.8
Exploit prediction
EPSS 0.1%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

317460317a02a1af512697e6e964298dedd8a1636.9
Vendor states this is fixed in 8a08635656037aee9c12231ed384449c4ffb1a93 (fixed)
Vendor states this is fixed in 90453eaf8f14e7be0ab03983f2a93aeb6b990a58 (fixed)
Vendor states this is fixed in a968dffa5ab3c74d2ebb3a6233bf8b843f0bfc20 (fixed)
Vendor states this is fixed in b5a71cb2db6d84ac0042549dcec266b18429d41e (fixed)
Vendor states this is fixed in 6.12.110 (unaffected)
Vendor states this is fixed in 6.18.52 (unaffected)
Vendor states this is fixed in 6.9 (unaffected)
Vendor states this is fixed in 7.2.6 (unaffected)
Vendor states this is fixed in 7.3 (unaffected)
Vendor states this is fixed in 7.3-rc1 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusRECEIVED

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card