CVE-2026-23056

CVE-2026-23056 is a security vulnerability that is still awaiting full analysis and scoring. 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: uacce: implement mremap in uacce_vm_ops to return -EPERM The current uacce_vm_ops does not support the mremap operation of vm_operations_struct. Implement .mremap to return -EPERM to remind users. The reason we need to explicitly disable mremap is that when the driver does not implement .mremap, it uses the default mremap method. This could lead to a risk scenario: An application might first mmap address p1, then mremap to p2, followed by munmap(p1), and finally munmap(p2). Since the default mremap copies the original vma's vm_private_data (i.e., q) to the new vma, both munmap operations would trigger vma_close, causing q->qfr to be freed twice(qfr will be set to null here, so repeated release is ok).

Frequently asked questions

What is CVE-2026-23056?
In the Linux kernel, the following vulnerability has been resolved: uacce: implement mremap in uacce_vm_ops to return -EPERM The current uacce_vm_ops does not support the mremap operation of vm_operations_struct. Implement .mremap to return -EPERM to remind users. The reason we need to explicitly disable mremap is that when the driver does not implement .mremap, it uses the default mremap method. This could lead to a risk scenario: An application might first mmap address p1, then mremap to p2, followed by munmap(p1), and finally munmap(p2). Since the default mremap copies the original vma's vm_private_data (i.e., q) to the new vma, both munmap operations would trigger vma_close, causing q->qfr to be freed twice(qfr will be set to null here, so repeated release is ok).
Is CVE-2026-23056 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-23056?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-23056 have an EU (EUVD) identifier?
Yes. CVE-2026-23056 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5488.
When was CVE-2026-23056 published?
CVE-2026-23056 was published on 2026-02-04 and last updated on 2026-06-17.

References