openEuler update for kernel

Published: 2021-09-30

Risk	Low
Patch available	YES
Number of vulnerabilities	3
CVE-ID	CVE-2021-40490 CVE-2021-3653 CVE-2021-22543
CWE-ID	CWE-362 CWE-264 CWE-119
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #3 is available.
Vulnerable software Subscribe	openEuler Operating systems & Components / Operating system perf Operating systems & Components / Operating system package or component python3-perf Operating systems & Components / Operating system package or component kernel-source Operating systems & Components / Operating system package or component kernel-devel Operating systems & Components / Operating system package or component kernel-debugsource Operating systems & Components / Operating system package or component kernel-tools Operating systems & Components / Operating system package or component python2-perf-debuginfo Operating systems & Components / Operating system package or component python2-perf Operating systems & Components / Operating system package or component bpftool Operating systems & Components / Operating system package or component kernel-tools-devel Operating systems & Components / Operating system package or component kernel-debuginfo Operating systems & Components / Operating system package or component python3-perf-debuginfo Operating systems & Components / Operating system package or component bpftool-debuginfo Operating systems & Components / Operating system package or component kernel-tools-debuginfo Operating systems & Components / Operating system package or component perf-debuginfo Operating systems & Components / Operating system package or component kernel Operating systems & Components / Operating system package or component
Vendor	openEuler

Security Bulletin

This security bulletin contains information about 3 vulnerabilities.

1) Race condition

EUVDB-ID: #VU63667

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-2021-40490

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 ext4_write_inline_data_end in fs/ext4/inline.c in the ext4 subsystem in the Linux kernel. 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 repository.

Vulnerable software versions

openEuler: 20.03 LTS SP1 - 20.03 LTS SP2

perf: before 4.19.90-2109.7.0.0112

python3-perf: before 4.19.90-2109.7.0.0112

kernel-source: before 4.19.90-2109.7.0.0112

kernel-devel: before 4.19.90-2109.7.0.0112

kernel-debugsource: before 4.19.90-2109.7.0.0112

kernel-tools: before 4.19.90-2109.7.0.0112

python2-perf-debuginfo: before 4.19.90-2109.7.0.0112

python2-perf: before 4.19.90-2109.7.0.0112

bpftool: before 4.19.90-2109.7.0.0112

kernel-tools-devel: before 4.19.90-2109.7.0.0112

kernel-debuginfo: before 4.19.90-2109.7.0.0112

python3-perf-debuginfo: before 4.19.90-2109.7.0.0112

bpftool-debuginfo: before 4.19.90-2109.7.0.0112

kernel-tools-debuginfo: before 4.19.90-2109.7.0.0112

perf-debuginfo: before 4.19.90-2109.7.0.0112

kernel: before 4.19.90-2109.7.0.0112

External links

http://www.openeuler.org/en/security/security-bulletins/detail/?id=openEuler-SA-2021-1366

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.

2) Security restrictions bypass

EUVDB-ID: #VU56904

Risk: Low

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-3653

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a malicious guest to escalate privileges on the system.

The vulnerability exists due to improperly imposed security restrictions within the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) for the L2 guest.

As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

openEuler: 20.03 LTS SP1 - 20.03 LTS SP2

perf: before 4.19.90-2109.7.0.0112

python3-perf: before 4.19.90-2109.7.0.0112

kernel-source: before 4.19.90-2109.7.0.0112

kernel-devel: before 4.19.90-2109.7.0.0112

kernel-debugsource: before 4.19.90-2109.7.0.0112

kernel-tools: before 4.19.90-2109.7.0.0112

python2-perf-debuginfo: before 4.19.90-2109.7.0.0112

python2-perf: before 4.19.90-2109.7.0.0112

bpftool: before 4.19.90-2109.7.0.0112

kernel-tools-devel: before 4.19.90-2109.7.0.0112

kernel-debuginfo: before 4.19.90-2109.7.0.0112

python3-perf-debuginfo: before 4.19.90-2109.7.0.0112

bpftool-debuginfo: before 4.19.90-2109.7.0.0112

kernel-tools-debuginfo: before 4.19.90-2109.7.0.0112

perf-debuginfo: before 4.19.90-2109.7.0.0112

kernel: before 4.19.90-2109.7.0.0112

External links

http://www.openeuler.org/en/security/security-bulletins/detail/?id=openEuler-SA-2021-1366

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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

3) Buffer overflow

EUVDB-ID: #VU56018

Risk: Low

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

CVE-ID: CVE-2021-22543

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

Description

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

The vulnerability exists due to a boundary error in Linux kernel when handling VM_IO|VM_PFNMAP vmas in KVM. A local user can can bypass RO checks and cause the pages to get freed while still accessible by the VMM and guest. As a result, an attacker with the ability to start and control a VM to read/write random pages of memory, can trigger memory corruption and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

openEuler: 20.03 LTS SP1 - 20.03 LTS SP2

perf: before 4.19.90-2109.7.0.0112

python3-perf: before 4.19.90-2109.7.0.0112

kernel-source: before 4.19.90-2109.7.0.0112

kernel-devel: before 4.19.90-2109.7.0.0112

kernel-debugsource: before 4.19.90-2109.7.0.0112

kernel-tools: before 4.19.90-2109.7.0.0112

python2-perf-debuginfo: before 4.19.90-2109.7.0.0112

python2-perf: before 4.19.90-2109.7.0.0112

bpftool: before 4.19.90-2109.7.0.0112

kernel-tools-devel: before 4.19.90-2109.7.0.0112

kernel-debuginfo: before 4.19.90-2109.7.0.0112

python3-perf-debuginfo: before 4.19.90-2109.7.0.0112

bpftool-debuginfo: before 4.19.90-2109.7.0.0112

kernel-tools-debuginfo: before 4.19.90-2109.7.0.0112

perf-debuginfo: before 4.19.90-2109.7.0.0112

kernel: before 4.19.90-2109.7.0.0112

External links

http://www.openeuler.org/en/security/security-bulletins/detail/?id=openEuler-SA-2021-1366

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.