CVE-2023-53713

Local privilege escalation via SME context overwrite

Published Oct 22, 2025 · Updated Oct 22, 2025

Out-of-bounds write in the Linux kernel allows local users to corrupt kernel memory through an arm64 SME context save. The fpsimd_save path clears a variable-size FFR context field with an unconditional 8-byte store, leaving bytes uncleared or overwriting the following allocation when the SME vector length differs from 64 bytes. An unprivileged process on an SME-capable arm64 system can select the vector length, enter streaming mode, and force a context switch, enabling disclosure, privilege escalation, or a crash.

CVSS severity7.8
High
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Out-of-bounds write in the Linux kernel allows local users to corrupt kernel memory through an arm64 SME context save. The fpsimd_save path clears a variable-size FFR context field with an unconditional 8-byte store, leaving bytes uncleared or overwriting the following allocation when the SME vector length differs from 64 bytes. An unprivileged process on an SME-capable arm64 system can select the vector length, enter streaming mode, and force a context switch, enabling disclosure, privilege escalation, or a crash.

The record

CVE
CVE-2023-53713
Published
Oct 22, 2025
Updated
Oct 22, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 22, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 22, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=5.16
  2. Affected versionversion=9f5848665788a0f07bc175cb2cdd06d367b7556e <1403a899153a12d93fd510e463fd6d0eafba4336
  3. Affected versionversion=9f5848665788a0f07bc175cb2cdd06d367b7556e <8769a62faacbbb6cac5e35d9047ce445183d4e9f
  4. Affected versionversion=9f5848665788a0f07bc175cb2cdd06d367b7556e <893b24181b4c4bf1fa2841b1ed192e5413a97cb1
  5. Affected versionversion=9f5848665788a0f07bc175cb2cdd06d367b7556e <97669214944e80d3756657c21c4f286f3da6a423

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.16; version=9f5848665788a0f07bc175cb2cdd06d367b7556e <1403a899153a12d93fd510e463fd6d0eafba4336; version=9f5848665788a0f07bc175cb2cdd06d367b7556e <8769a62faacbbb6cac5e35d9047ce445183d4e9f; version=9f5848665788a0f07bc175cb2cdd06d367b7556e <893b24181b4c4bf1fa2841b1ed192e5413a97cb1; version=9f5848665788a0f07bc175cb2cdd06d367b7556e <97669214944e80d3756657c21c4f286f3da6a423

Published CVSS scores

7.8Linux Kernel CNACVSS: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.

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

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.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo