SB2021050604 - Red Hat Enterprise Linux 7 update for kernel-alt
Published: May 6, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Resource management error (CVE-ID: CVE-2020-11669)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to resource management issue. A local user of guest operating system can perform a denial of service attack against the POWER9 KVM host.
2) Use-after-free (CVE-ID: CVE-2021-3347)
The vulnerability allows a local user to elevate privileges on the system.
The vulnerability exists due to a use-after-free error when handling PI futexes. A local user can run a specially crafted program to trigger a use-after-free error and execute arbitrary code with elevated privileges.
3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-27364)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to iscsi_if_recv_msg() allows non-root users to connect and send commands to the Linux kernel. A local user can escalate privileges on the system.
4) Buffer overflow (CVE-ID: CVE-2021-27365)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing Netlink messages in Linux kernel through 5.11.3, as certain iSCSI data structures do not have appropriate length constraints or checks, and can exceed the PAGE_SIZE value. A local unprivileged user can send a Netlink message that is associated with iSCSI, and has a length up to the maximum length of a Netlink message, trigger memory corruption and execute arbitrary code on the system with elevated privileges.
Remediation
Install update from vendor's website.