Linux Kernel up to 6.18.20/6.19.10 mm/damon/sysfs damon_sysfs_new_test_ctx memory leak

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.20/6.19.10. It has been classified as critical. The affected element is the function damon_sysfs_new_test_ctx of the file mm/damon/sysfs. Performing a manipulation results in memory leak. This vulnerability is identified as CVE-2026-31459. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.20/6.19.10. It has been classified as critical. This affects the function damon_sysfs_new_test_ctx of the file mm/damon/sysfs. The manipulation with an unknown input leads to a memory leak vulnerability. CWE is classifying the issue as CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. 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/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure Patch series "mm/damon/sysfs: fix memory leak and NULL dereference issues", v4. DAMON_SYSFS can leak memory under allocation failure, and do NULL pointer dereference when a privileged user make wrong sequences of control. Fix those. This patch (of 3): When damon_sysfs_new_test_ctx() fails in damon_sysfs_commit_input(), param_ctx is leaked because the early return skips the cleanup at the out label. Destroy param_ctx before returning.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-31459 since 03/09/2026. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 310609 (Linux Distros Unpatched Vulnerability : CVE-2026-31459), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.18.21 or 6.19.11 eliminates this vulnerability. Applying the patch e9de9f3ce06b133a348006668bc8d25c6e504867/f76f0a964bc3d7b7e253b43c669c41356bc54e71/7fe000eb32904758a85e62f6ea9483f89d5dabfc 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 (310609) and CERT Bund (WID-SEC-2026-1252). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• Siemens SIMATIC S7
• Proxmox Virtual Environment

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8
• 6.19.9
• 6.19.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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

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