CVE Catalog

CVE-2026-93137

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

6th percentile - higher than 6% of all known CVEs

Summary

In the Linux kernel, bpf_find_vma() reads task->mm and calls mmap_read_trylock() without holding a reference to mm_struct. For a foreign task, concurrent exit_mm() can free the mm_struct between the read and the trylock, leading to use-after-free. The fix pins the mm under task->alloc_lock and uses mmput_async(), rejecting irqs-disabled contexts and !CONFIG_MMU.

Risk Assessment

Risk of use-after-free in the kernel, potentially leading to system crash or privilege escalation.

Recommendation

Apply the Linux kernel update containing this fix to eliminate the use-after-free in bpf_find_vma().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix use-after-free on mm_struct in bpf_find_vma() bpf_find_vma() reads task->mm and calls mmap_read_trylock(mm) without holding a reference on the mm. On a foreign task, a concurrent exit_mm() can free the mm_struct between the lockless read and the trylock, resulting in a use-after-free. mm_struct is not SLAB_TYPESAFE_BY_RCU. For the current task, task->mm is stable. For a foreign task, pin the mm under task->alloc_lock and release it with mmput_async(), mirroring commit d8e27d2d22b6 ("bpf: fix mm lifecycle in open-coded task_vma iterator"). Use spin_trylock() instead of get_task_mm() so BPF context does not block on alloc_lock. Reject irqs-disabled contexts and !CONFIG_MMU on the foreign-task path because dropping the mm reference is not safe there. Race: CPU0 (BPF program) CPU1 (exiting task) ============================ ========================== bpf_find_vma(foreign_task): mm = task->mm exit_mm(): task->mm = NULL mmput(mm) -> frees mm_struct mmap_read_trylock(mm) // UAF on mm

Vulnerability data from NVD (NIST) · CISA KEV · EPSS