CVE-2025-21840

thermal/netlink: Prevent userspace segmentation fault by adjusting UAPI header

Description

In the Linux kernel, the following vulnerability has been resolved: thermal/netlink: Prevent userspace segmentation fault by adjusting UAPI header The intel-lpmd tool [1], which uses the THERMAL_GENL_ATTR_CPU_CAPABILITY attribute to receive HFI events from kernel space, encounters a segmentation fault after commit 1773572863c4 ("thermal: netlink: Add the commands and the events for the thresholds"). The issue arises because the THERMAL_GENL_ATTR_CPU_CAPABILITY raw value was changed while intel_lpmd still uses the old value. Although intel_lpmd can be updated to check the THERMAL_GENL_VERSION and use the appropriate THERMAL_GENL_ATTR_CPU_CAPABILITY value, the commit itself is questionable. The commit introduced a new element in the middle of enum thermal_genl_attr, which affects many existing attributes and introduces potential risks and unnecessary maintenance burdens for userspace thermal netlink event users. Solve the issue by moving the newly introduced THERMAL_GENL_ATTR_TZ_PREV_TEMP attribute to the end of the enum thermal_genl_attr. This ensures that all existing thermal generic netlink attributes remain unaffected. [ rjw: Subject edits ]

N/A
CVSS
Severity:
EPSS 0.03%
Affected: Linux Linux
Affected: Linux Linux
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2025-21840?
CVE-2025-21840 has not yet been assigned a CVSS score.
How to fix CVE-2025-21840?
To fix CVE-2025-21840, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2025-21840 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-21840 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2025-21840?
CVE-2025-21840 affects Linux Linux, Linux Linux.
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