SB2022041271 - Red Hat Enterprise Linux 7.7 update for kernel

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2021-4083)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the Linux kernel's garbage collection for Unix domain socket file handlers. A local user can call close() and fget() simultaneously and can potentially trigger a race condition, which in turn leads to a use-after-free error and allows privilege escalation.

2) Use-after-free (CVE-ID: CVE-2021-0920)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the unix_scm_to_skb() function of af_unix.c in Linux kernel. A local user can run a specially crafted program to trigger a race condition and execute arbitrary code with elevated privileges.

3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2022-22942)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to an error in the vmwgfx driver in Linux kernel. A local unprivileged user can gain access to files opened by other processes on the system through a dangling 'file' pointer.

Exploiting this vulnerability requires an attacker to have access to either /dev/dri/card0 or /dev/dri/rendererD128 and be able to issue an ioctl() on the resulting file descriptor.

4) Use-after-free (CVE-ID: CVE-2021-4028)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error in the RDMA listen() function in Linux kernel. A local user can run a specially crafted program to trigger a use-after-free error and execute arbitrary code with elevated privileges.

Remediation

Install update from vendor's website.

References

• https://access.redhat.com/errata/RHSA-2022:1324