Information disclosure in Linux kernel - CVE-2019-15031

Vulnerability identifier: #VU28403

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2019-15031

CWE-ID: CWE-200

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local authenticated user to #BASIC_IMPACT#.

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 MSR_TM_ACTIVE is misused in arch/powerpc/kernel/process.c.

Linux kernel
Red Hat Enterprise Linux for IBM System z (Structure A)
Red Hat Enterprise Linux for Power 9
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
Red Hat Enterprise Linux for x86_64
Red Hat CodeReady Linux Builder for x86_64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
kernel-alt (Red Hat package)
kernel (Red Hat package)

Install update from vendor's website.

Linux kernel - addressed in versions 4.19.73, 5.3
kernel-alt (Red Hat package) - update to 4.14.0-115.19.1.el7a
kernel (Red Hat package) - update to 4.18.0-147.8.1.el8_1

• https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.73
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.2.15
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3

• Information disclosure in Linux kernel
• Red Hat Enterprise Linux 8 update for kernel
• Red Hat Enterprise Linux 7 update for kernel-alt