SB2020061019 - Red Hat Enterprise Linux 8 update for kernel
Published: June 10, 2020
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2019-18660)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to absent protection in Linux kernel on powerpc against the Spectre-RSB, related to arch/powerpc/kernel/entry_64.S and arch/powerpc/kernel/security.c. A local user can gain unauthorized access to sensitive information on the system.
2) NULL pointer dereference (CVE-ID: CVE-2020-10711)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in the Linux kernel's SELinux subsystem when importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated.
A remote attacker can send specially crafted packets the affected system, trigger a NULL pointer dereference error and crash the Linux kernel.
3) Race condition (CVE-ID: CVE-2020-11884)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/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 authenticated user to execute arbitrary code.
In the Linux kernel through 5.6.7 on the s390 platform, code execution may occur because of a race condition, as demonstrated by code in enable_sacf_uaccess in arch/s390/lib/uaccess.c that fails to protect against a concurrent page table upgrade, aka CID-3f777e19d171. A crash could also occur.
4) Use-after-free (CVE-ID: CVE-2020-12657)
CWE-ID: CWE-416 - Use After Free
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 compromise vulnerable system.
The vulnerability exists due to a use-after-free error in "block/bfq-iosched.c" file related to "bfq_idle_slice_timer_body". A local user can execute arbitrary code on the target system.
Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.
5) Information disclosure (CVE-ID: CVE-2020-0543)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to incomplete cleanup from specific special register read operations in some Intel(R) Processors. A local user can gain unauthorized access to sensitive information on the system.
Remediation
Install update from vendor's website.