CVE-2019-15031: Infoleak
A flaw in the Linux kernel on the PowerPC platform, was found where a local user can read vector registers of other user processes (during a hardware interrupt). An attacker must start a transaction when the FPU operation begins or there is no leakage. Vector registers will become corrupted with values from the different local Linux processes, because of the missing check inside arch/powerpc/kernel/process.c. The highest threat from this vulnerability is confidentiality of data and availability of the system.
Other sources
In the Linux kernel through 5.2.14 on the powerpc platform, a local user can read vector registers of other users' processes via an interrupt. To exploit the venerability, a local user starts a transaction (via the hardware transactional memory instruction tbegin) and then accesses vector registers. At some point, the vector registers will be corrupted with the values from a different local Linux process, because MSRTMACTIVE is misused in arch/powerpc/kernel/process.c.
In the Linux kernels through 5.2.14 on the powerpc platform, a local user can read vector registers of other users processes via an interrupt. To exploit the vulnerability, a local user starts a transaction (via the hardware transactional memory instruction tbegin) and then accesses vector registers. At some point, the vector registers will be corrupted with the values from a different local Linux process because of a misused check in arch/powerpc/kernel/process.c. However, the attacker cannot predict when it happens. The only mitigation for this issue: not using FPU completely (then can use emulation instead).
References: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a8318c13e79badb92bc6640704a64cc022a6eb97
— Red Hat
Affected Software
Remediation
Information
Patch Available
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2019-15031?
CVE-2019-15031 is classified as a medium severity vulnerability affecting the Linux kernel on the PowerPC platform.
How do I fix CVE-2019-15031?
To mitigate CVE-2019-15031, users should update their Linux kernel to the specified fixed versions, such as 0:4.14.0-115.19.1.el7a for Red Hat or appropriate versions for Debian and Ubuntu.
Who is affected by CVE-2019-15031?
CVE-2019-15031 affects local users on systems running vulnerable versions of the Linux kernel on the PowerPC platform.
Can CVE-2019-15031 lead to data leakage?
Yes, CVE-2019-15031 allows local users to read vector registers of other user processes, potentially leading to sensitive data leakage.
When was CVE-2019-15031 disclosed?
CVE-2019-15031 was disclosed in 2019, highlighting a security flaw in the Linux kernel affecting PowerPC systems.