Use-after-free error in Linux kernel - CVE-2017-15126

Vulnerability identifier: #VU12265

CSH Severity: High

CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2017-15126

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The weakness exists in fs/userfaultfd.c due to the handling of fork failure when dealing with event messages. Failure to fork correctly can lead to a situation where a fork event will be removed from an already freed list of events with userfaultfd_ctx_put(). A remote attacker can trigger use-after-free error and execute arbitrary code.

Successful exploitation of the vulnerability may result in system compromise.

Linux kernel
Red Hat Enterprise Linux Desktop
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux Server
Red Hat Enterprise Linux Workstation
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for Power, big endian
Red Hat Enterprise Linux for Scientific Computing
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for Real Time

kernel (Red Hat package)
kernel-rt (Red Hat package)
Red Hat Virtualization Host

Update to version 4.13.6.

kernel (Red Hat package) - update to 3.10.0-862.el7
kernel-rt (Red Hat package) - update to 3.10.0-862.rt56.804.el7

• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=384632e67e0829deb8015e...

• Remote code execution in Linux Kernel
• Red Hat update for kernel
• Red Hat update for kernel-rt