CVE-2023-52926

Privilege escalation via io_uring provided-buffer use-after-free

Published Feb 24, 2025 · Updated Aug 5, 2026

Use-after-free in Linux io_uring allows local users to escalate privileges through crafted provided-buffer IORING_OP_READ requests. When a read returns a negative error other than -EAGAIN or -EIOCBQUEUED, IORING_OP_READ fails to consume the buffer list before io_rw_done completes in another context. Unprivileged local syscall access is sufficient; successful exploitation can disclose or corrupt kernel memory, gain elevated privileges, or panic the host.

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 io_uring allows local users to escalate privileges through crafted provided-buffer IORING_OP_READ requests. When a read returns a negative error other than -EAGAIN or -EIOCBQUEUED, IORING_OP_READ fails to consume the buffer list before io_rw_done completes in another context. Unprivileged local syscall access is sufficient; successful exploitation can disclose or corrupt kernel memory, gain elevated privileges, or panic the host.

The record

CVE
CVE-2023-52926
Published
Feb 24, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 24, 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=2b188cc1bb857a9d4701ae59aa7768b5124e262e <6c27fc6a783c8a77c756dd5461b15e465020d075
  2. Affected versionversion=2b188cc1bb857a9d4701ae59aa7768b5124e262e <72060434a14caea20925e492310d6e680e3f9007
  3. Affected versionversion=2b188cc1bb857a9d4701ae59aa7768b5124e262e <a08d195b586a217d76b42062f88f375a3eedda4d
  4. Affected versionversion=5.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2b188cc1bb857a9d4701ae59aa7768b5124e262e <6c27fc6a783c8a77c756dd5461b15e465020d075; version=2b188cc1bb857a9d4701ae59aa7768b5124e262e <72060434a14caea20925e492310d6e680e3f9007; version=2b188cc1bb857a9d4701ae59aa7768b5124e262e <a08d195b586a217d76b42062f88f375a3eedda4d; version=5.1

Published CVSS scores

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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