---
id: CVE-2026-64507
title: 'x86/bugs: Enable IBPB flush on BPF JIT allocation'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86/bugs: Enable IBPB flush on BPF JIT allocation

  Enable hardening against JIT spraying when Spectre-v2 mitigations are in
  use. Specifically, issue an IBPB flush on BP…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    25dbcd31781e2bc3cd63d873af1fcd06f863a126
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    cb27f3bf915cc0f20fc0c48da9059304e39ebd35
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    9354248fc1c33a844ca1872761f6668b393e8c37
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    8a4c8af9ae67eb072d90d1b339f14d27a82bd2a1
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    52440e15d9628f8f239373c0f2e5e8f92feea2df
  - >-
    Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 <
    a3af84b0fa00ead01fcd0e28b5d773ff25990a0d
  - Linux 5.18
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:40:39.454506Z'
exploitAvailable: true
published: '2026-07-25'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T16:44:55.807Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-64507'
references:
  - url: 'https://git.kernel.org/stable/c/25dbcd31781e2bc3cd63d873af1fcd06f863a126'
  - url: 'https://git.kernel.org/stable/c/cb27f3bf915cc0f20fc0c48da9059304e39ebd35'
  - url: 'https://git.kernel.org/stable/c/9354248fc1c33a844ca1872761f6668b393e8c37'
  - url: 'https://git.kernel.org/stable/c/8a4c8af9ae67eb072d90d1b339f14d27a82bd2a1'
  - url: 'https://git.kernel.org/stable/c/52440e15d9628f8f239373c0f2e5e8f92feea2df'
  - url: 'https://git.kernel.org/stable/c/a3af84b0fa00ead01fcd0e28b5d773ff25990a0d'
tags:
  - cve.org
  - exploit-available
epss: 0.00231
epssPercentile: 0.14023
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/manalejandro/CVE-2026-64507'
  checkedAt: '2026-11-08T19:28:28.558Z'
ingestedAt: '2026-11-06T16:57:43.158Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

x86/bugs: Enable IBPB flush on BPF JIT allocation

Enable hardening against JIT spraying when Spectre-v2 mitigations are in
use. Specifically, issue an IBPB flush on BPF JIT memory reuse. Skip
enabling the IBPB flush if the BPF dispatcher is already using a retpoline
sequence.

This hardening applies only when BPF-JIT is in use. Guard the enabling
under CONFIG_BPF_JIT so that bugs.c still builds with CONFIG_BPF_JIT=n.

## Affected

- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < 25dbcd31781e2bc3cd63d873af1fcd06f863a126`
- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < cb27f3bf915cc0f20fc0c48da9059304e39ebd35`
- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < 9354248fc1c33a844ca1872761f6668b393e8c37`
- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < 8a4c8af9ae67eb072d90d1b339f14d27a82bd2a1`
- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < 52440e15d9628f8f239373c0f2e5e8f92feea2df`
- `Linux >= 57631054fae6dcc9c892ae6310b58bbb6f6e5048 < a3af84b0fa00ead01fcd0e28b5d773ff25990a0d`
- `Linux 5.18`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.