Linux Kernel up to 6.18.29/7.0.6/7.1-rc2 pseries copy_to_user hdr memory leak

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.29/7.0.6/7.1-rc2. It has been rated as critical. Affected is the function copy_to_user of the component pseries. The manipulation of the argument hdr leads to memory leak. This vulnerability is referenced as CVE-2026-46182. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.29/7.0.6/7.1-rc2. It has been rated as critical. This issue affects the function copy_to_user of the component pseries. The manipulation of the argument hdr with an unknown input leads to a memory leak vulnerability. Using CWE to declare the problem leads to CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: pseries/papr-hvpipe: Prevent kernel stack memory leak to userspace The hdr variable is allocated on the stack and only hdr.version and hdr.flags are initialized explicitly. Because the struct papr_hvpipe_hdr contains reserved padding bytes (reserved[3] and reserved2[40]), these could leak the uninitialized bytes to userspace after copy_to_user(). This patch fixes that by initializing the whole struct to 0.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-46182 since 05/13/2026. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 6.18.30, 7.0.7 or 7.1-rc3 eliminates this vulnerability. Applying the patch 0479b6e9f999cc1cbad7d9f09f574fc387e605d5/f88f8e4485b437e0a2f96a7ff1f88aa22d925659/cefeed44296261173a806bef988b26bc565da4be 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.

Be aware that VulDB is the high quality source for vulnerability data.

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
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3
• 7.0.4
• 7.0.5
• 7.0.6
• 7.1-rc1
• 7.1-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion