SB2021060329 - Ubuntu update for linux 



SB2021060329 - Ubuntu update for linux

Published: June 3, 2021

Security Bulletin ID SB2021060329
Severity
High
Patch available
YES
Number of vulnerabilities 6
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

High 17% Low 83%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 6 secuirty vulnerabilities.


1) Use-after-free (CVE-ID: CVE-2020-25670)

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

The vulnerability exists due to a use-after-free error in the NFC LLCP protocol implementation. A local user can perform manipulation with an unknown input for the llcp_sock_bind() function to crash or escalate their privileges on the system.


2) Use-after-free (CVE-ID: CVE-2020-25671)

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

The vulnerability exists due to a use-after-free error in the NFC LLCP protocol implementation. A local user can trigger the llcp_sock_connect() function to crash or escalate their privileges on the system.


3) Memory leak (CVE-ID: CVE-2020-25672)

The vulnerability allows a remote attacker to perform DoS attack on the target system.

The vulnerability exists due memory leak in the NFC LLCP protocol implementation when triggering the llcp_sock_connect() function. A remote attacker can force the application to leak memory and perform denial of service attack.


4) Resource exhaustion (CVE-ID: CVE-2020-25673)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper control consumption of internal resources in non-blocking socket in llcp_sock_connect() function. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.


5) Out-of-bounds read (CVE-ID: CVE-2021-29155)

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists in retrieve_ptr_limit in kernel/bpf/verifier.c in the Linux kernel mechanism. A local, special user privileged (CAP_SYS_ADMIN) BPF program running on affected systems may bypass the protection, and execute speculatively out-of-bounds loads from the kernel memory.


6) Out-of-bounds write (CVE-ID: CVE-2021-3501)

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

The vulnerability exists due to a boundary error in the KVM API in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and escalate privileges on the system.


Remediation

Install update from vendor's website.