CVE-2025-38724Network attack vector

Kernel compromise via NFS client-expiry race

Published Sep 4, 2025 · Updated Aug 5, 2026

Use-after-free in the Linux NFSv4 server allows remote attackers to compromise the kernel through SETCLIENTID_CONFIRM requests. nfsd4_setclientid_confirm() continues after get_client_locked() fails to acquire a reference while a confirmed client expires, then accesses the freed client object. Any host able to reach TCP port 2049 can trigger the attacker-widened race without file-handle or export access, enabling kernel-memory disclosure or modification, control-flow hijacking, a panic, or an unkillable hung task.

CVSS severity9.8
Critical
EPSS probability0.38%
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 the Linux NFSv4 server allows remote attackers to compromise the kernel through SETCLIENTID_CONFIRM requests. nfsd4_setclientid_confirm() continues after get_client_locked() fails to acquire a reference while a confirmed client expires, then accesses the freed client object. Any host able to reach TCP port 2049 can trigger the attacker-widened race without file-handle or export access, enabling kernel-memory disclosure or modification, control-flow hijacking, a panic, or an unkillable hung task.

The record

CVE
CVE-2025-38724
Published
Sep 4, 2025
Updated
Aug 5, 2026
Vendor
Siemens
Product
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
Classifications
CWE-416, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 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

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=V3.1.5 <*

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Siemens · SIPLUS S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.5 <*
The Linux Kernel Organization · Linuxversion=3.17; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <22f45cedf281e6171817c8a3432c44d788c550e1; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <36e83eda90e0e4ac52f259f775b40b2841f8a0a3; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <3f252a73e81aa01660cb426735eab932e6182e8d; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <571a5e46c71490285d2d8c06f6b5a7cbf6c7edd1; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <74ad36ed60df561a303a19ecef400c7096b20306; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <908e4ead7f757504d8b345452730636e298cbf68; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <d35ac850410966010e92f401f4e21868a9ea4d8b; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <d71abd1ae4e0413707cd42b10c24a11d1aa71772; version=d20c11d86d8f821a64eac7d6c8f296f06d935f4f <f3aac6cf390d8b80e1d82975faf4ac61175519c0
Siemens · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPversion=V3.1.5 <*
Siemens · SIMATIC CN 4100version=0 <V5.0
Siemens · SIMATIC S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.5 <*

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.8Linux kernel CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.8Siemens ProductCERTCVSS: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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1210Exploitation of Remote Services

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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