CVE-2025-22036

Local privilege escalation via exFAT buffer use-after-free

Published Apr 16, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel exFAT allows local users to corrupt kernel stack memory through reads from a mounted exFAT volume. In fs/exfat/inode.c, exfat_get_block calls bh_read on a stack-allocated buffer_head; deferred put_bh then decrements its reference count after the stack object has expired. An unprivileged account needs read/write access to an already-mounted exFAT volume and can drive the race to crash the kernel or escalate privileges.

CVSS severity7.8
High
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel exFAT allows local users to corrupt kernel stack memory through reads from a mounted exFAT volume. In fs/exfat/inode.c, exfat_get_block calls bh_read on a stack-allocated buffer_head; deferred put_bh then decrements its reference count after the stack object has expired. An unprivileged account needs read/write access to an already-mounted exFAT volume and can drive the race to crash the kernel or escalate privileges.

The record

CVE
CVE-2025-22036
Published
Apr 16, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, CWE-362, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 16, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=11a347fb6cef62ce47e84b97c45f2b2497c7593b <1bb7ff4204b6d4927e982cd256286c09ed4fd8ca
  2. Affected versionversion=11a347fb6cef62ce47e84b97c45f2b2497c7593b <49b0a6ab8e528a0c1c50e37cef9b9c7c121365f2
  3. Affected versionversion=11a347fb6cef62ce47e84b97c45f2b2497c7593b <f7447286363dc1e410bf30b87d75168f3519f9cc
  4. Affected versionversion=11a347fb6cef62ce47e84b97c45f2b2497c7593b <f807a6bf2005740fa26b4f59c4a003dc966b9afd
  5. Affected versionversion=6.8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=11a347fb6cef62ce47e84b97c45f2b2497c7593b <1bb7ff4204b6d4927e982cd256286c09ed4fd8ca; version=11a347fb6cef62ce47e84b97c45f2b2497c7593b <49b0a6ab8e528a0c1c50e37cef9b9c7c121365f2; version=11a347fb6cef62ce47e84b97c45f2b2497c7593b <f7447286363dc1e410bf30b87d75168f3519f9cc; version=11a347fb6cef62ce47e84b97c45f2b2497c7593b <f807a6bf2005740fa26b4f59c4a003dc966b9afd; version=6.8

Published CVSS scores

7.8kernel.orgCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.0NIST NVDCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
7.0CISA-ADPCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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