CVE-2025-21718

Kernel compromise via ROSE timer use-after-free

Published Feb 27, 2025 · Updated Sep 8, 2026

Use-after-free in Linux and Siemens S7-1500 MFP controllers allows local users to compromise the kernel through AF_ROSE socket calls. ROSE timers take the socket spinlock without checking whether a user thread owns the socket, so timer expiry can race socket operations and dereference freed memory in rose_timer_expiry. Exploitation requires local low-privileged access and available AF_ROSE support; successful exploitation can expose or alter kernel memory or crash the system.

CVSS severity7.8
High
EPSS probability0.17%
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 and Siemens S7-1500 MFP controllers allows local users to compromise the kernel through AF_ROSE socket calls. ROSE timers take the socket spinlock without checking whether a user thread owns the socket, so timer expiry can race socket operations and dereference freed memory in rose_timer_expiry. Exploitation requires local low-privileged access and available AF_ROSE support; successful exploitation can expose or alter kernel memory or crash the system.

The record

CVE
CVE-2025-21718
Published
Feb 27, 2025
Updated
Sep 8, 2026
Vendor
Siemens
Product
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
Classifications
CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 27, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 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=V3.1.6 <*

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Siemens · SIPLUS S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.6 <*
The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0d5bca3be27bfcf8f980f2fed49b6cbb7dafe4a1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1409b45d4690308c502c6caf22f01c3c205b4717; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1992fb261c90e9827cf5dc3115d89bb0853252c9; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <51c128ba038cf1b79d605cbee325919b45ab95a5; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <52f5aff33ca73b2c2fa93f40a3de308012e63cf4; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <58051a284ac18a3bb815aac6289a679903ddcc3f; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5de7665e0a0746b5ad7943554b34db8f8614a196; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f55c88e3ca5939a6a8a329024aed8f3d98eea8e4; version=2.6.12
Siemens · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPversion=V3.1.6 <*
Siemens · SIMATIC S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.6 <*

Published CVSS scores

7.0Siemens ProductCERTCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/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 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

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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