SB2021051158 - Ubuntu update for linux

Description

This security bulletin contains information about 9 vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2021-20292)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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

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.

2) Resource management error (CVE-ID: CVE-2021-26930)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 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

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.

3) Allocation of resources without limits or throttling (CVE-ID: CVE-2021-26931)

CWE-ID: CWE-770 - Allocation of Resources Without Limits or Throttling

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

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

The vulnerability exists due to allocation of resources without limits or throttling error within the scsiback_gnttab_data_map_batch() function in drivers/xen/xen-scsiback.c. A local user can perform a denial of service (DoS) attack.

4) Allocation of resources without limits or throttling (CVE-ID: CVE-2021-28038)

CWE-ID: CWE-770 - Allocation of Resources Without Limits or Throttling

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

The vulnerability allows a local user to a crash the entire system.

The vulnerability exists due to allocation of resources without limits or throttling error within the xenvif_tx_action() function in drivers/net/xen-netback/netback.c. A local user can a crash the entire system.

5) Improper Initialization (CVE-ID: CVE-2021-28688)

CWE-ID: CWE-665 - Improper Initialization

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

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

The vulnerability exists due to improper initialization of pointers such that subsequent cleanup code wouldn't use uninitialized or stale values. A local user can perform a denial of service attack.

6) Input validation error (CVE-ID: CVE-2021-29264)

CWE-ID: CWE-20 - Improper input validation

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

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

The vulnerability exists due to improper input validation within the gfar_add_rx_frag() and gfar_clean_rx_ring() functions in drivers/net/ethernet/freescale/gianfar.c. A local user can perform a denial of service (DoS) attack.

7) Race condition (CVE-ID: CVE-2021-29265)

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:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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

The vulnerability exists due to a race condition within the usbip_sockfd_store() function in drivers/usb/usbip/stub_dev.c. A local user can perform a denial of service (DoS) attack.

8) Buffer overflow (CVE-ID: CVE-2021-29650)

CWE-ID: CWE-119 - Memory corruption

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

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

The vulnerability exists due to a boundary error within the netfilter subsystem in net/netfilter/x_tables.c and include/linux/netfilter/x_tables.h. A local user can trigger memory corruption upon the assignment of a new table value and cause denial of service.

9) Memory leak (CVE-ID: CVE-2021-30002)

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

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

The vulnerability allows a local user to perform DoS attack on the target system.

The vulnerability exists due memory leak within the webcam support driver in video_usercopy() function in drivers/media/v4l2-core/v4l2-ioctl.c in Linux kernel. A local user can trigger leak memory and perform denial of service attack.

Remediation

Install update from vendor's website.

References

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