ALINUX2-SA-2019%3A0049

Package updates are available for Alibaba Cloud Linux 2.1903 that fix the following vulnerabilities: CVE-2019-1125: An information disclosure vulnerability exists when certain central processing units (CPU) speculatively access memory, aka 'Windows Kernel Information Disclosure Vulnerability'. This CVE ID is unique from CVE-2019-1071, CVE-2019-1073. CVE-2018-20669: An issue where a provided address with access_ok() is not checked was discovered in i915_gem_execbuffer2_ioctl in drivers/gpu/drm/i915/i915_gem_execbuffer.c in the Linux kernel through 4.19.13. A local attacker can craft a malicious IOCTL function call to overwrite arbitrary kernel memory, resulting in a Denial of Service or privilege escalation. CVE-2018-18397: The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes), related to fs/userfaultfd.c and mm/userfaultfd.c. CVE-2019-13272: In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.