Ubuntu update for linux

Published: 2021-05-11

Risk	Medium
Patch available	YES
Number of vulnerabilities	9
CVE-ID	CVE-2021-20292 CVE-2021-26930 CVE-2021-26931 CVE-2021-28038 CVE-2021-28688 CVE-2021-29264 CVE-2021-29265 CVE-2021-29650 CVE-2021-30002
CWE-ID	CWE-416 CWE-399 CWE-770 CWE-665 CWE-20 CWE-362 CWE-119 CWE-401
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Ubuntu Operating systems & Components / Operating system linux-image-oem (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-oracle (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-gke (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-gcp (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-azure (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-virtual-hwe-16.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-lowlatency-hwe-16.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-generic-hwe-16.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-aws-hwe (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-virtual (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-snapdragon (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-raspi2 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-oracle-lts-18.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-lowlatency (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-kvm (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-generic-lpae (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-generic (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-gcp-lts-18.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-dell300x (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-azure-lts-18.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-aws-lts-18.04 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-143-lowlatency (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-143-generic-lpae (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-143-generic (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1114-azure (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1102-snapdragon (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1102-aws (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1099-gcp (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1091-kvm (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1085-raspi2 (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1071-oracle (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-4.15.0-1018-dell300x (Ubuntu package) Operating systems & Components / Operating system package or component
Vendor	Canonical Ltd.

Security Bulletin

This security bulletin contains information about 9 vulnerabilities.

1) Use-after-free

EUVDB-ID: #VU63382

Risk: Low

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-20292

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges.

The vulnerability exists due to a use-after-free error in drivers/gpu/drm/nouveau/nouveau_sgdma.c in nouveau_sgdma_create_ttm in Nouveau DRM subsystem. A local user can escalate privileges and execute code in the context of the kernel.

Mitigation

Update the affected package linux to the latest version.

Vulnerable software versions

Ubuntu: 14.04 - 18.04

linux-image-oem (Ubuntu package): before 5.4.0.202.198

linux-image-oracle (Ubuntu package): before 6.8.0-1017.18~22.04.1

linux-image-gke (Ubuntu package): before 6.8.0-1015.19

linux-image-gcp (Ubuntu package): before 6.8.0-1019.21~22.04.1

linux-image-azure (Ubuntu package): before 6.8.0-1018.21~22.04.1

linux-image-virtual-hwe-16.04 (Ubuntu package): before 4.15.0.210.193

linux-image-lowlatency-hwe-16.04 (Ubuntu package): before 4.15.0.210.193

linux-image-generic-hwe-16.04 (Ubuntu package): before 4.15.0.210.193

linux-image-aws-hwe (Ubuntu package): before Ubuntu Pro (Infra-only)

linux-image-virtual (Ubuntu package): before 4.15.0.143.130

linux-image-snapdragon (Ubuntu package): before 4.15.0.1102.105

linux-image-raspi2 (Ubuntu package): before 4.15.0.1085.82

linux-image-oracle-lts-18.04 (Ubuntu package): before 4.15.0.1071.81

linux-image-lowlatency (Ubuntu package): before 4.15.0.143.130

linux-image-kvm (Ubuntu package): before 4.15.0.1091.87

linux-image-generic-lpae (Ubuntu package): before 4.15.0.143.130

linux-image-generic (Ubuntu package): before 4.15.0.143.130

linux-image-gcp-lts-18.04 (Ubuntu package): before 4.15.0.1099.117

linux-image-dell300x (Ubuntu package): before 4.15.0.1018.20

linux-image-azure-lts-18.04 (Ubuntu package): before 4.15.0.1114.87

linux-image-aws-lts-18.04 (Ubuntu package): before 4.15.0.1102.105

linux-image-4.15.0-143-lowlatency (Ubuntu package): before 4.15.0-143.147

linux-image-4.15.0-143-generic-lpae (Ubuntu package): before 4.15.0-143.147

linux-image-4.15.0-143-generic (Ubuntu package): before 4.15.0-143.147

linux-image-4.15.0-1114-azure (Ubuntu package): before 4.15.0-1114.127

linux-image-4.15.0-1102-snapdragon (Ubuntu package): before 4.15.0-1102.111

linux-image-4.15.0-1102-aws (Ubuntu package): before 4.15.0-1102.109

linux-image-4.15.0-1099-gcp (Ubuntu package): before 4.15.0-1099.112

linux-image-4.15.0-1091-kvm (Ubuntu package): before 4.15.0-1091.93

linux-image-4.15.0-1085-raspi2 (Ubuntu package): before 4.15.0-1085.90

linux-image-4.15.0-1071-oracle (Ubuntu package): before 4.15.0-1071.79

linux-image-4.15.0-1018-dell300x (Ubuntu package): before 4.15.0-1018.22

CPE2.3

External links

https://ubuntu.com/security/notices/USN-4946-1

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) Resource management error

EUVDB-ID: #VU51587

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-26930

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

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

The vulnerability exists due to improper management of internal resources when processing service requests to the PV backend within drivers/block/xen-blkback/blkback.c driver in Xen. A local user on the guest OS can perform a denial of service (DoS) attack.