Red Hat Enterprise Linux 8.1 Extended Update Support update for kernel

1) Race condition

EUVDB-ID: #VU54292

Risk: Medium

CVSSv3.1: 7.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-3609

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

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

The vulnerability exists due to a race condition in the CAN BCM networking protocol (net/can/bcm.c) in the Linux kernel ranging from version 2.6.25 to mainline 5.13-rc6. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for ARM 64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 8.1

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 8.1

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 8.1

kernel (Red Hat package): before 4.18.0-147.54.2.el8_1

External links

http://access.redhat.com/errata/RHSA-2021:3444

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

2) Use-after-free

EUVDB-ID: #VU56393

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-3715

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error in the "Routing decision" classifier in the Linux kernel's Traffic Control networking subsystem (route4_change() function in net/sched/cls_route.c) in the way it handled changing of classification filters. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for ARM 64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 8.1

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 8.1

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 8.1

kernel (Red Hat package): before 4.18.0-147.54.2.el8_1

External links

http://access.redhat.com/errata/RHSA-2021:3444

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Out-of-bounds write

EUVDB-ID: #VU57101

Risk: Medium

CVSSv3.1: 7 [CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-37576

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support: 8.1

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for ARM 64 - Extended Update Support: 8.1

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 8.1

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 8.1

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 8.1

kernel (Red Hat package): before 4.18.0-147.54.2.el8_1

External links

http://access.redhat.com/errata/RHSA-2021:3444

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.