SB2021081247 - SUSE update for the Linux Kernel
Published: August 12, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 secuirty vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2021-21781)
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output in the ARM SIGPAGE functionality. A userland application can read the contents of the sigpage, which can leak kernel memory contents.
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) Integer overflow (CVE-ID: CVE-2021-33909)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to integer overflow during size_t-to-int conversion when creating, mounting, and deleting a deep directory structure whose total path length exceeds 1GB. An unprivileged local user can write up to 10-byte string to an offset of exactly -2GB-10B below the beginning of a vmalloc()ated kernel buffer.
Successful exploitation of vulnerability may allow an attacker to exploit the our-of-bounds write vulnerability to execute arbitrary code with root privileges.
4) NULL pointer dereference (CVE-ID: CVE-2021-3659)
The vulnerability allows a local usre to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in the way the user closes the LR-WPAN connection within the IEEE 802.15.4 wireless networking subsystem. A local user can perform a denial of service (DoS) attack.
5) 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.