CVE-2026-80685

Received Received - Intake

Memory Corruption in Linux Kernel Snapshot Page Handling

Publication date: 2026-08-28

Last updated on: 2026-08-29

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: mm/util: don't read __page_2 for order-1 folios in snapshot_page() snapshot_page() currently reads __page_2 after checking nr_pages > 1, but it should only do so when nr_pages > 2. If an order-1 folio is allocated at the end of a vmemmap section, __page_2 will not exist and reading it will cause a fault. During DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed on the page isolation path while reading an order-1 folio's __page_2 from an adjacent absent section (unmapped vmemmap). Fix this to avoid reading memmap that doesn't exist (e.g., a vmemmap hole).

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-28

Last Modified

2026-08-29

Generated

2026-09-17

AI Q&A

2026-08-28

EPSS Evaluated

2026-09-15

NVD

CVE-2026-80685

EUVD

EUVD-2026-67561

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability is in the Linux kernel's memory management code. It occurs in the snapshot_page() function when handling order-1 folios. The function incorrectly reads __page_2 when nr_pages is greater than 1, but it should only do so when nr_pages is greater than 2. This causes a fault if an order-1 folio is allocated at the end of a vmemmap section where __page_2 does not exist.

Detection Guidance

This vulnerability is specific to the Linux kernel and manifests during memory operations, particularly on ppc64le systems. Detection requires checking kernel logs for oops or faults related to snapshot_page() or memory removal operations. Monitor dmesg or system logs for errors during memory hotplug or vmemmap operations.

Impact Analysis

This vulnerability can cause system crashes or kernel oopses, particularly during memory operations like DLPAR memory removal on large systems. It may lead to unexpected system behavior or downtime if exploited.

Compliance Impact

This vulnerability does not directly affect compliance with standards like GDPR or HIPAA. It is a Linux kernel memory management issue that could cause system crashes during memory operations, potentially leading to data corruption or unavailability. Such instability may indirectly impact compliance by disrupting data processing or storage systems.

Mitigation Strategies

Apply the kernel patch that fixes this issue. Avoid performing DLPAR memory remove operations on affected systems until patched. Monitor kernel updates from your Linux distribution and update to a version containing the fix.

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