SB2021100618 - Red Hat Enterprise Linux 7.4 update for kernel
Published: October 6, 2021 Updated: February 8, 2024
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Race condition (CVE-ID: CVE-2021-32399)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition for removal of the HCI controller within net/bluetooth/hci_request.c in the Linux kernel. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.
2) Buffer overflow (CVE-ID: CVE-2021-22543)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in Linux kernel when handling VM_IO|VM_PFNMAP vmas in KVM. A local user can can bypass RO checks and cause the pages to get freed while still accessible by the VMM and guest. As a result, an attacker with the ability to start and control a VM to read/write random pages of memory, can trigger memory corruption and execute arbitrary code with elevated privileges.
3) Out-of-bounds write (CVE-ID: CVE-2021-22555)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input in net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
4) Out-of-bounds write (CVE-ID: CVE-2021-37576)
The vulnerability allows a remote user to escalate privileges on the system.
The vulnerability exists due to a boundary error in arch/powerpc/kvm/book3s_rtas.c in the Linux kernel through 5.13.5 on the powerpc platform. An attacker on KVM guest OS can cause host OS memory corruption via rtas_args.nargs and execute arbitrary code on the host OS.
Remediation
Install update from vendor's website.