CVE-2022-49995

Local privilege escalation via writeback use-after-free

Published Jun 18, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel 5.15 through 5.15.63 and 5.16 through 5.19.5 allows local users to escalate privileges. wb_inode_writeback_end() can schedule bandwidth-estimation delayed work after bdi_unregister has completed, causing its timer to access a freed bdi_writeback object. A low-privileged user with writable removable storage can drive the race through writeback and device removal, enabling kernel-memory access or a kernel panic.

CVSS severity7.8
High
EPSS probability0.23%
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 5.15 through 5.15.63 and 5.16 through 5.19.5 allows local users to escalate privileges. wb_inode_writeback_end() can schedule bandwidth-estimation delayed work after bdi_unregister has completed, causing its timer to access a freed bdi_writeback object. A low-privileged user with writable removable storage can drive the race through writeback and device removal, enabling kernel-memory access or a kernel panic.

The record

CVE
CVE-2022-49995
Published
Jun 18, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 18, 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=45a2966fd64147518dc5bca25f447bd0fb5359ac <9a6c710f3bc10bc9cc23e1c080b53245b7f9d5b7
  2. Affected versionversion=45a2966fd64147518dc5bca25f447bd0fb5359ac <f87904c075515f3e1d8f4a7115869d3b914674fd
  3. Affected versionversion=45a2966fd64147518dc5bca25f447bd0fb5359ac <f96b9f7c1676923bce871e728bb49c0dfa5013cc
  4. Affected versionversion=5.15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=45a2966fd64147518dc5bca25f447bd0fb5359ac <9a6c710f3bc10bc9cc23e1c080b53245b7f9d5b7; version=45a2966fd64147518dc5bca25f447bd0fb5359ac <f87904c075515f3e1d8f4a7115869d3b914674fd; version=45a2966fd64147518dc5bca25f447bd0fb5359ac <f96b9f7c1676923bce871e728bb49c0dfa5013cc; version=5.15

Published CVSS scores

7.8CanonicalCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
7.8LinuxCVSS:3.1/AV:L/AC:L/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.

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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
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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