CVE-2025-39944

Local kernel compromise via delayed-work use-after-free

Published Oct 4, 2025 · Updated Oct 4, 2025

Use-after-free in the Linux OcteonTX2 PTP driver allows local users to corrupt kernel memory during device teardown. otx2_ptp_destroy frees the PTP object after cancel_delayed_work returns while the cyclic otx2_sync_tstamp callback can remain active and dereference it. Reaching the race requires local CAP_NET_ADMIN access to timestamp configuration and teardown; exploitation can disclose or modify kernel memory, hijack control flow, or panic the kernel.

CVSS severity7.8
High
EPSS probability0.15%
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 OcteonTX2 PTP driver allows local users to corrupt kernel memory during device teardown. otx2_ptp_destroy frees the PTP object after cancel_delayed_work returns while the cyclic otx2_sync_tstamp callback can remain active and dereference it. Reaching the race requires local CAP_NET_ADMIN access to timestamp configuration and teardown; exploitation can disclose or modify kernel memory, hijack control flow, or panic the kernel.

The record

CVE
CVE-2025-39944
Published
Oct 4, 2025
Updated
Oct 4, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-825, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 4, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 4, 2025Record 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=2958d17a898416c6193431676f6130b68a2cb9fc <2786879aebf363806a13d41e8d5f99202ddd23d9
  2. Affected versionversion=2958d17a898416c6193431676f6130b68a2cb9fc <5ca20bb7b4bde72110c3ae78423cbfdd0157aa36
  3. Affected versionversion=2958d17a898416c6193431676f6130b68a2cb9fc <d2cfefa14ce8137b17f99683f968bebf134b6a48
  4. Affected versionversion=2958d17a898416c6193431676f6130b68a2cb9fc <f8b4687151021db61841af983f1cb7be6915d4ef
  5. Affected versionversion=2958d17a898416c6193431676f6130b68a2cb9fc <ff27e23b311fed4d25e3852e27ba693416d4c7b3
  6. Affected versionversion=6.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2958d17a898416c6193431676f6130b68a2cb9fc <2786879aebf363806a13d41e8d5f99202ddd23d9; version=2958d17a898416c6193431676f6130b68a2cb9fc <5ca20bb7b4bde72110c3ae78423cbfdd0157aa36; version=2958d17a898416c6193431676f6130b68a2cb9fc <d2cfefa14ce8137b17f99683f968bebf134b6a48; version=2958d17a898416c6193431676f6130b68a2cb9fc <f8b4687151021db61841af983f1cb7be6915d4ef; version=2958d17a898416c6193431676f6130b68a2cb9fc <ff27e23b311fed4d25e3852e27ba693416d4c7b3; version=6.1

Published CVSS scores

7.8Linux kernel CVE teamCVSS: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-825Expired Pointer Dereference
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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