CVE-2025-38383: 
Linux Kernel vulnerability analysis and mitigation

CVE-2025-38383 is a data race vulnerability discovered in the Linux kernel's mm/vmalloc subsystem, specifically in the shownumainfo() function. The vulnerability was disclosed on July 25, 2025, affecting the vmallocinfoshow functionality. The issue occurs due to a read/write data race where m->private is accessible to multiple CPUs simultaneously (NVD, RedHat).

The vulnerability manifests as a data race condition in the shownumainfo() function where concurrent read and write operations occur on the memory address 0xffff88800971fe30. The issue involves 4-byte operations across different CPU cores, with one task (8289 on CPU 0) performing a read operation while another task (8287 on CPU 1) performs a write operation, resulting in value changes from 0x0000008f to 0x00000000. The vulnerability has been assigned a CVSS v3.1 score of 7.0 with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H (RedHat).

The vulnerability could potentially lead to data corruption or inconsistent system state due to the race condition in memory management operations. The high CVSS score indicates significant potential impact on system confidentiality, integrity, and availability when successfully exploited (RedHat).

The fix involves modifying the heap allocation strategy in vmallocinfoshow(). Instead of allocating the heap in procvmallocinit() and passing the heap address to m->private, the solution implements heap allocation directly within vmallocinfoshow() (NVD).

Ubuntu has classified this vulnerability as medium priority and has begun implementing fixes across various kernel versions. Several Linux distributions, including Red Hat Enterprise Linux, have assessed their systems and provided status updates for affected versions (Ubuntu).