Ubuntu 20.04 LTS / 20.10 : Linux kernel vulnerabilities (USN-4949-1)

high Nessus Plugin ID 149411
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Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 20.04 LTS / 20.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4949-1 advisory.

- A NULL pointer dereference flaw was found in the Linux kernel's GPU Nouveau driver functionality in versions prior to 5.12-rc1 in the way the user calls ioctl DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC. This flaw allows a local user to crash the system. (CVE-2020-25639)

- An issue was discovered in the Linux kernel 3.11 through 5.10.16, as used by Xen. To service requests to the PV backend, the driver maps grant references provided by the frontend. In this process, errors may be encountered. In one case, an error encountered earlier might be discarded by later processing, resulting in the caller assuming successful mapping, and hence subsequent operations trying to access space that wasn't mapped. In another case, internal state would be insufficiently updated, preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c. (CVE-2021-26930)

- An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen. Block, net, and SCSI backends consider certain errors a plain bug, deliberately causing a kernel crash. For errors potentially being at least under the influence of guests (such as out of memory conditions), it isn't correct to assume a plain bug. Memory allocations potentially causing such crashes occur only when Linux is running in PV mode, though. This affects drivers/block/xen-blkback/blkback.c and drivers/xen/xen-scsiback.c.
(CVE-2021-26931)

- An issue was discovered in the Linux kernel through 5.11.6. fastrpc_internal_invoke in drivers/misc/fastrpc.c does not prevent user applications from sending kernel RPC messages, aka CID-20c40794eb85. This is a related issue to CVE-2019-2308. (CVE-2021-28375)

- An issue was discovered in the Linux kernel through 5.11.10. drivers/net/ethernet/freescale/gianfar.c in the Freescale Gianfar Ethernet driver allows attackers to cause a system crash because a negative fragment size is calculated in situations involving an rx queue overrun when jumbo packets are used and NAPI is enabled, aka CID-d8861bab48b6. (CVE-2021-29264)

- An issue was discovered in the Linux kernel before 5.11.7. usbip_sockfd_store in drivers/usb/usbip/stub_dev.c allows attackers to cause a denial of service (GPF) because the stub-up sequence has race conditions during an update of the local and shared status, aka CID-9380afd6df70.
(CVE-2021-29265)

- An issue was discovered in the Linux kernel before 5.11.9. drivers/vhost/vdpa.c has a use-after-free because v->config_ctx has an invalid value upon re-opening a character device, aka CID-f6bbf0010ba0.
(CVE-2021-29266)

- An issue was discovered in the Linux kernel before 5.11.11. tipc_nl_retrieve_key in net/tipc/node.c does not properly validate certain data sizes, aka CID-0217ed2848e8. (CVE-2021-29646)

- An issue was discovered in the Linux kernel before 5.11.11. The netfilter subsystem allows attackers to cause a denial of service (panic) because net/netfilter/x_tables.c and include/linux/netfilter/x_tables.h lack a full memory barrier upon the assignment of a new table value, aka CID-175e476b8cdf.
(CVE-2021-29650)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-4949-1

Plugin Details

Severity: High

ID: 149411

File Name: ubuntu_USN-4949-1.nasl

Version: 1.4

Type: local

Agent: unix

Published: 5/12/2021

Updated: 9/3/2021

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

CVSS Score Source: CVE-2021-3491

VPR

Risk Factor: Critical

Score: 9.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6

Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:F/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 8.2

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Temporal Vector: E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.10, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1024-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1024-raspi-nolpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1027-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1029-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1031-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1032-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-1033-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-53-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-53-generic-64k, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-53-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.8.0-53-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-gke, p-cpe:/a:canonical:ubuntu_linux:linux-image-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi-nolpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-20.04-edge

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/11/2021

Vulnerability Publication Date: 2/16/2021

Exploitable With

Metasploit (Linux eBPF ALU32 32-bit Invalid Bounds Tracking LPE)

Reference Information

CVE: CVE-2020-25639, CVE-2021-3489, CVE-2021-3490, CVE-2021-3491, CVE-2021-26930, CVE-2021-26931, CVE-2021-28375, CVE-2021-29264, CVE-2021-29265, CVE-2021-29266, CVE-2021-29646, CVE-2021-29650

USN: 4949-1