CVE-2025-39859
published 2025-09-19CVE-2025-39859: In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only…
PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.5th percentile
In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
The ptp_ocp_detach() only shuts down the watchdog timer if it is
pending. However, if the timer handler is already running, the
timer_delete_sync() is not called. This leads to race conditions
where the devlink that contains the ptp_ocp is deallocated while
the timer handler is still accessing it, resulting in use-after-free
bugs. The following details one of the race scenarios.
(thread 1) | (thread 2)
ptp_ocp_remove() |
ptp_ocp_detach() | ptp_ocp_watchdog()
if (timer_pending(&bp->watchdog))| bp = timer_container_of()
timer_delete_sync() |
|
devlink_free(devlink) //free |
| bp-> //use
Resolve this by unconditionally calling timer_delete_sync() to ensure
the timer is reliably deactivated, preventing any access after free.
Affected
17 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.16.6-1 (forky) | linux 6.16.6-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 773bda96492153e11d21eb63ac814669b51fc701 < f10d3c7267ac7387a5129d5506c3c5f2460cfd9b | f10d3c7267ac7387a5129d5506c3c5f2460cfd9b |
| linux | linux | >= 773bda96492153e11d21eb63ac814669b51fc701 < 8bf935cf789872350b04c1a6468b0a509f67afb2 | 8bf935cf789872350b04c1a6468b0a509f67afb2 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.16.6-1 | 6.16.6-1 |
| linux | linux_kernel | >= 5.15 < 6.16.6 | 6.16.6 |
| msrc | azl3_kernel_6.6.104.2-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.112.1-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.117.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.121.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.126.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.130.1-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| msrc | cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_msrc5.5MEDIUM
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GHSA
GHSA-fq5x-p5vr-m6pg: In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
The ptp_ocp_detach
ghsa_unreviewed·2025-09-22
CVE-2025-39859 [HIGH] CWE-416 GHSA-fq5x-p5vr-m6pg: In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
The ptp_ocp_detach
In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
The ptp_ocp_detach() only shuts down the watchdog timer if it is
pending. However, if the timer handler is already running, the
timer_delete_sync() is not called. This leads to race conditions
where the devlink that contains the ptp_ocp is deallocated while
the timer handler is still accessing it, resulting in use-after-free
bugs. The following details one of the race scenarios.
(thread 1) | (thread 2)
ptp_ocp_remove() |
ptp_ocp_detach() | ptp_ocp_watchdog()
if (timer_pending(&bp->watchdog))| bp = timer_container_of()
timer_delete_sync() |
|
devlink_free(devlink) //free |
| bp-> //use
Resolve this by unconditionally calling timer_delete_sync() to ensure
the
OSV
CVE-2025-39859: In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach()
osv·2025-09-19·CVSS 7.8
CVE-2025-39859 [HIGH] CVE-2025-39859: In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach()
In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only shuts down the watchdog timer if it is pending. However, if the timer handler is already running, the timer_delete_sync() is not called. This leads to race conditions where the devlink that contains the ptp_ocp is deallocated while the timer handler is still accessing it, resulting in use-after-free bugs. The following details one of the race scenarios. (thread 1) | (thread 2) ptp_ocp_remove() | ptp_ocp_detach() | ptp_ocp_watchdog() if (timer_pending(&bp->watchdog))| bp = timer_container_of() timer_delete_sync() | | devlink_free(devlink) //free | | bp-> //use Resolve this by unconditionally calling timer_delete_sync() to ensure the time
Red Hat
kernel: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
vendor_redhat·2025-09-19·CVSS 7.8
CVE-2025-39859 [HIGH] kernel: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
kernel: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
The ptp_ocp_detach() only shuts down the watchdog timer if it is
pending. However, if the timer handler is already running, the
timer_delete_sync() is not called. This leads to race conditions
where the devlink that contains the ptp_ocp is deallocated while
the timer handler is still accessing it, resulting in use-after-free
bugs. The following details one of the race scenarios.
(thread 1) | (thread 2)
ptp_ocp_remove() |
ptp_ocp_detach() | ptp_ocp_watchdog()
if (timer_pending(&bp->watchdog))| bp = timer_container_of()
timer_delete_sync() |
|
devlink_free(devlink) //free |
| bp-> //use
Resolve
Microsoft
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
vendor_msrc·2025-09-09·CVSS 5.5
CVE-2025-39859 [HIGH] ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Debian
CVE-2025-39859: linux - In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: f...
vendor_debian·2025·CVSS 7.8
CVE-2025-39859 [HIGH] CVE-2025-39859: linux - In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: f...
In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only shuts down the watchdog timer if it is pending. However, if the timer handler is already running, the timer_delete_sync() is not called. This leads to race conditions where the devlink that contains the ptp_ocp is deallocated while the timer handler is still accessing it, resulting in use-after-free bugs. The following details one of the race scenarios. (thread 1) | (thread 2) ptp_ocp_remove() | ptp_ocp_detach() | ptp_ocp_watchdog() if (timer_pending(&bp->watchdog))| bp = timer_container_of() timer_delete_sync() | | devlink_free(devlink) //free | | bp-> //use Resolve this by unconditionally calling timer_delete_sync() to ensure the time
No detection rules found.
No public exploits indexed.
2025-09-19
Published