SB2020120320 - Ubuntu update for linux
Published: December 3, 2020 Updated: April 23, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 10 secuirty vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2020-14351)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error within the perf subsystem. A local user with permission to monitor perf events cam corrupt memory and execute arbitrary code with elevated privileges.
2) Out-of-bounds read (CVE-ID: CVE-2020-14390)
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to an out-of-bounds read that occurs leading to memory corruption or a denial of service. This highest threat from this vulnerability is to system availability.
3) Buffer overflow (CVE-ID: CVE-2020-25211)
The vulnerability allows a local user to crash the system.
The vulnerability exists due to a boundary error within the ctnetlink_parse_tuple_filter() function in net/netfilter/nf_conntrack_netlink.c. A local user can inject conntrack netlink configuration, trigger buffer overflow and crash the kernel or force usage of incorrect protocol numbers.
4) Incorrect authorization (CVE-ID: CVE-2020-25284)
The vulnerability allows a local privileged user to manipulate data.
The vulnerability exists due to incorrect authorization error within the rbd_config_info_show(), rbd_image_refresh(), do_rbd_add() and do_rbd_remove() functions in drivers/block/rbd.c. A local privileged user can manipulate data.
5) NULL pointer dereference (CVE-ID: CVE-2020-25285)
The vulnerability allows a local privileged user to execute arbitrary code.
The vulnerability exists due to NULL pointer dereference within the allowed_mems_nr(), hugetlb_sysctl_handler_common() and hugetlb_overcommit_handler() functions in mm/hugetlb.c. A local privileged user can execute arbitrary code.
6) Infinite loop (CVE-ID: CVE-2020-25641)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to incorrect implementation of biovecs in Linux kernel. A zero-length biovec request issued by the block subsystem could cause the kernel to enter an infinite loop, causing a denial of service. A local user can issue requests to a block device and perform a denial of service (DoS) attack.
7) Out-of-bounds read (CVE-ID: CVE-2020-25643)
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to a boundary condition within the HDLC_PPP module of the Linux kernel in the ppp_cp_parse_cr() function. A remote authenticated user can trigger out-of-bounds read error and read contents of memory on the system.
8) Cleartext transmission of sensitive information (CVE-ID: CVE-2020-25645)
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to traffic passed between two Geneve endpoints with configured IPsec can be unencrypted for the specific UDP port. A remote attacker with ability to intercept network traffic can gain access to sensitive data.
9) Buffer Over-read (CVE-ID: CVE-2020-28915)
The vulnerability allows a local user with physical access to perform a denial of service attack.
The vulnerability exists due to an out-of-bounds (OOB) memory access flaw in fbcon_get_font() function in drivers/video/fbdev/core/fbcon.c in fbcon driver module in the Linux kernel. A local user with special user privilege and with physical access can gain access to out-of-bounds memory, leading to a system crash or a leak of internal kernel information.
10) Information disclosure (CVE-ID: CVE-2020-4788)
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists in IBM Power9 processors due to unspecified error. A local user can obtain sensitive information from the data in the L1 cache under extenuating circumstances.
Remediation
Install update from vendor's website.