NULL pointer dereference in Linux
CVE-2025-38522
In the Linux kernel, the following vulnerability has been resolved: sched/ext: Prevent update_locked_rq() calls with NULL rq Avoid invoking update_locked_rq() when the runqueue (rq) pointer is NULL in the SCX_CALL_OP and SCX_CALL_OP_RET macros. Previously, calling update_locked_rq(NULL) with preemption enabled could trigger the following warning: BUG: using __this_cpu_write() in preemptible [00000000] This happens because __this_cpu_write() is unsafe to use in preemptible context. rq is NULL when an ops invoked from an unlocked context. In such cases, we don't need to store any rq, since the value should already be NULL (unlocked). Ensure that update_locked_rq() is only called when rq is non-NULL, preventing calling __this_cpu_write() on preemptible context.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.001 (2.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 3rd percentile — 2.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000
Affected products
- Linux — versions 18853ba782bef65fc81ef2b3370382e5b479c5eb, 6.15, 0
- Linux Kernel — versions 6.15, 6.16
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-38522?
- CVE-2025-38522 is a medium-severity vulnerability in Linux, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2025-08-16.
- How severe is CVE-2025-38522?
- Medium severity. CVSS v3 base score is 5.5 out of 10.