CVE-2025-40248

Local kernel compromise via vsock connect race

Published Dec 4, 2025 · Updated Aug 5, 2026

Race condition in affected Linux kernels since 3.9 and RUGGEDCOM RST2428P before V4.0 allows local users to corrupt kernel memory. During an established connect, signal or timeout handling disconnects the socket while concurrent sendmsg or connect operations retain and use transport state, causing stale state, a use-after-free, or a null-pointer dereference. An unprivileged local process can create AF_VSOCK sockets and repeatedly control both sides of the race; consequences include kernel memory read or write, control-flow hijack, a hang, or a crash.

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

What happened

Race condition in affected Linux kernels since 3.9 and RUGGEDCOM RST2428P before V4.0 allows local users to corrupt kernel memory. During an established connect, signal or timeout handling disconnects the socket while concurrent sendmsg or connect operations retain and use transport state, causing stale state, a use-after-free, or a null-pointer dereference. An unprivileged local process can create AF_VSOCK sockets and repeatedly control both sides of the race; consequences include kernel memory read or write, control-flow hijack, a hang, or a crash.

The record

CVE
CVE-2025-40248
Published
Dec 4, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-20, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 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

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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=3.9
  2. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <002541ef650b742a198e4be363881439bb9d86b4
  3. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <3f71753935d648082a8279a97d30efe6b85be680
  4. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <5998da5a8208ae9ad7838ba322bccb2bdcd95e81
  5. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <67432915145848658149683101104e32f9fd6559
  6. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <ab6b19f690d89ae4709fba73a3c4a7911f495b7a
  7. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <da664101fb4a0de5cb70d2bae6a650df954df2af
  8. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <eeca93f06df89be5a36305b7b9dae1ed65550dfc
  9. Affected versionversion=d021c344051af91f42c5ba9fdedc176740cbd238 <f1c170cae285e4b8f61be043bb17addc3d0a14b5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3.9; version=d021c344051af91f42c5ba9fdedc176740cbd238 <002541ef650b742a198e4be363881439bb9d86b4; version=d021c344051af91f42c5ba9fdedc176740cbd238 <3f71753935d648082a8279a97d30efe6b85be680; version=d021c344051af91f42c5ba9fdedc176740cbd238 <5998da5a8208ae9ad7838ba322bccb2bdcd95e81; version=d021c344051af91f42c5ba9fdedc176740cbd238 <67432915145848658149683101104e32f9fd6559; version=d021c344051af91f42c5ba9fdedc176740cbd238 <ab6b19f690d89ae4709fba73a3c4a7911f495b7a; version=d021c344051af91f42c5ba9fdedc176740cbd238 <da664101fb4a0de5cb70d2bae6a650df954df2af; version=d021c344051af91f42c5ba9fdedc176740cbd238 <eeca93f06df89be5a36305b7b9dae1ed65550dfc; version=d021c344051af91f42c5ba9fdedc176740cbd238 <f1c170cae285e4b8f61be043bb17addc3d0a14b5
Siemens · RUGGEDCOM RST2428Pversion=0 <V4.0

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
7.0Siemens ProductCERTCVSS:3.1/AV:L/AC:H/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-20Improper Input Validation
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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