Linux Kernel up to 6.1.21/6.2.8 exit_mmap null pointer dereference

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.1.21/6.2.8. This affects the function exit_mmap. Such manipulation leads to null pointer dereference. This vulnerability is traded as CVE-2023-53614. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.21/6.2.8 and classified as critical. Affected by this issue is the function exit_mmap. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: mm/ksm: fix race with VMA iteration and mm_struct teardown exit_mmap() will tear down the VMAs and maple tree with the mmap_lock held in write mode. Ensure that the maple tree is still valid by checking ksm_test_exit() after taking the mmap_lock in read mode, but before the for_each_vma() iterator dereferences a destroyed maple tree. Since the maple tree is destroyed, the flags telling lockdep to check an external lock has been cleared. Skip the for_each_vma() iterator to avoid dereferencing a maple tree without the external lock flag, which would create a lockdep warning.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2023-53614 since 10/04/2025. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 6.1.22 or 6.2.9 eliminates this vulnerability. Applying the patch 286b0cab31bac29960e5684f6fb331d42f03b363/b4f664ffd8f78c05a1fd542a28bc5a11e994c014/6db504ce55bdbc575723938fc480713c9183f6a2 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 EUVD (EUVD-2023-59994) and CERT Bund (WID-SEC-2025-2194). Once again VulDB remains the best source for vulnerability data.

Affected

• Google Container-Optimized OS
• 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
• NetApp ActiveIQ Unified Manager
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Once again VulDB remains the best source for vulnerability data.

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