CVE-2026-53373

A flaw was found in the Linux kernel's memory management (mm/vma) component. When the mmap_prepare() hook is invoked from an mmap() operation, it can attempt to unmap a Virtual Memory Area (VMA) that is not fully established and already detached. This problematic behavior can lead to a warning in vma_mark_detached() and potentially cause system instability or unexpected behavior.

mmap_action_complete can be called from a compatibility mmap path where the VMA is not fully established in the maple tree and is already detached. If an mmap action returns an error, the old cleanup path can try to unmap that detached VMA even though the caller will clean it up, which can trigger a warning in vma_mark_detached. For the CVSS the PR:L is used because a local process must trigger the mmap path, but full administrative privileges are not clearly required. The issue is not network reachable and is driven by a local mmap operation through stacked driver or filesystem behavior. Impact is primarily denial of service through kernel warning or crash in hardened configurations such as panic_on_warn. No concrete UAF, OOB write, arbitrary write, or information leak primitive is demonstrated by the patch context.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.