Linux Kernel up to 6.6.112/6.12.53/6.17.3 pte_offset_map_lock infinite loop

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.112/6.12.53/6.17.3 and classified as critical. This affects the function pte_offset_map_lock. Performing a manipulation results in infinite loop. This vulnerability is identified as CVE-2025-40218. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.6.112/6.12.53/6.17.3. This affects the function pte_offset_map_lock. The manipulation with an unknown input leads to a infinite loop vulnerability. CWE is classifying the issue as CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mm/damon/vaddr: do not repeat pte_offset_map_lock() until success DAMON's virtual address space operation set implementation (vaddr) calls pte_offset_map_lock() inside the page table walk callback function. This is for reading and writing page table accessed bits. If pte_offset_map_lock() fails, it retries by returning the page table walk callback function with ACTION_AGAIN. pte_offset_map_lock() can continuously fail if the target is a pmd migration entry, though. Hence it could cause an infinite page table walk if the migration cannot be done until the page table walk is finished. This indeed caused a soft lockup when CPU hotplugging and DAMON were running in parallel. Avoid the infinite loop by simply not retrying the page table walk. DAMON is promising only a best-effort accuracy, so missing access to such pages is no problem.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-40218 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 277596 (Linux Distros Unpatched Vulnerability : CVE-2025-40218), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.113, 6.12.54 or 6.17.4 eliminates this vulnerability. Applying the patch 677ebfe5d00f94adec0c0204f6e6e2a82d3f77bf/ac42320ec873bfe726141069cfdd90ee5bc4e885/0ccd91cf749536d41307a07e60ec14ab0dbf21f5/b93af2cc8e036754c0d9970d9ddc47f43cc94b9f is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (277596) and CERT Bund (WID-SEC-2025-2747). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Microsoft Azure Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.112
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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