SB2021021624 - Red Hat Enterprise Linux 7.7 Extended Update Support update for kernel
Published: February 16, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Incorrect permission assignment for critical resource (CVE-ID: CVE-2020-24394)
CWE-ID: CWE-732 - Incorrect Permission Assignment for Critical Resource
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to bypass implemented security restrictions.
The vulnerability exists due to incorrect assignment of permissions on new filesystem objects when the filesystem lacks ACL support in fs/nfsd/vfs.c (in the NFS server). A local user can read and write arbitrary files on the system.
2) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2020-25212)
CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a TOCTOU mismatch in the NFS client code in the Linux kernel. A local user can run a specially crafted program to trigger memory corruption and execute arbitrary code on the system with elevated privileges.Remediation
Install update from vendor's website.