CVE-2025-37875

CVE-2025-37875 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: igc: fix PTM cycle trigger logic Writing to clear the PTM status 'valid' bit while the PTM cycle is triggered results in unreliable PTM operation. To fix this, clear the PTM 'trigger' and status after each PTM transaction. The issue can be reproduced with the following: $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to quickly reproduce the issue. PHC2SYS exits with: "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails This patch also fixes a hang in igc_probe() when loading the igc driver in the kdump kernel on systems supporting PTM. The igc driver running in the base kernel enables PTM trigger in igc_probe(). Therefore the driver is always in PTM trigger mode, except in brief periods when manually triggering a PTM cycle. When a crash occurs, the NIC is reset while PTM trigger is enabled. Due to a hardware problem, the NIC is subsequently in a bad busmaster state and doesn't handle register reads/writes. When running igc_probe() in the kdump kernel, the first register access to a NIC register hangs driver probing and ultimately breaks kdump. With this patch, igc has PTM trigger disabled most of the time, and the trigger is only enabled for very brief (10 - 100 us) periods when manually triggering a PTM cycle. Chances that a crash occurs during a PTM trigger are not 0, but extremely reduced.

Frequently asked questions

What is CVE-2025-37875?
In the Linux kernel, the following vulnerability has been resolved: igc: fix PTM cycle trigger logic Writing to clear the PTM status 'valid' bit while the PTM cycle is triggered results in unreliable PTM operation. To fix this, clear the PTM 'trigger' and status after each PTM transaction. The issue can be reproduced with the following: $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to quickly reproduce the issue. PHC2SYS exits with: "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails This patch also fixes a hang in igc_probe() when loading the igc driver in the kdump kernel on systems supporting PTM. The igc driver running in the base kernel enables PTM trigger in igc_probe(). Therefore the driver is always in PTM trigger mode, except in brief periods when manually triggering a PTM cycle. When a crash occurs, the NIC is reset while PTM trigger is enabled. Due to a hardware problem, the NIC is subsequently in a bad busmaster state and doesn't handle register reads/writes. When running igc_probe() in the kdump kernel, the first register access to a NIC register hangs driver probing and ultimately breaks kdump. With this patch, igc has PTM trigger disabled most of the time, and the trigger is only enabled for very brief (10 - 100 us) periods when manually triggering a PTM cycle. Chances that a crash occurs during a PTM trigger are not 0, but extremely reduced.
How severe is CVE-2025-37875?
CVE-2025-37875 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-37875 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-37875?
CVE-2025-37875 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-37875?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-37875 have an EU (EUVD) identifier?
Yes. CVE-2025-37875 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-14115.
When was CVE-2025-37875 published?
CVE-2025-37875 was published on 2025-05-09 and last updated on 2026-06-17.

References

Affected products (4)

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