Ubuntu 20.04 LTS : Linux kernel vulnerabilities (USN-5092-1)

high Nessus Plugin ID 153770

Synopsis

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

Description

The remote Ubuntu 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-5092-1 advisory.

- A lack of CPU resource in the Linux kernel tracing module functionality in versions prior to 5.14-rc3 was found in the way user uses trace ring buffer in a specific way. Only privileged local users (with CAP_SYS_ADMIN capability) could use this flaw to starve the resources causing denial of service.
(CVE-2021-3679)

- In kernel/bpf/verifier.c in the Linux kernel before 5.12.13, a branch can be mispredicted (e.g., because of type confusion) and consequently an unprivileged BPF program can read arbitrary memory locations via a side-channel attack, aka CID-9183671af6db. (CVE-2021-33624)

- In the Linux kernel through 5.13.7, an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack because the protection mechanism neglects the possibility of uninitialized memory locations on the BPF stack. (CVE-2021-34556)

- In the Linux kernel through 5.13.7, an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack because a certain preempting store operation does not necessarily occur before a store operation that has an attacker-controlled value.
(CVE-2021-35477)

- hso_free_net_device in drivers/net/usb/hso.c in the Linux kernel through 5.13.4 calls unregister_netdev without checking for the NETREG_REGISTERED state, leading to a use-after-free and a double free.
(CVE-2021-37159)

- arch/powerpc/kvm/book3s_rtas.c in the Linux kernel through 5.13.5 on the powerpc platform allows KVM guest OS users to cause host OS memory corruption via rtas_args.nargs, aka CID-f62f3c20647e. (CVE-2021-37576)

- ** DISPUTED ** In drivers/char/virtio_console.c in the Linux kernel before 5.13.4, data corruption or loss can be triggered by an untrusted device that supplies a buf->len value exceeding the buffer size. NOTE:
the vendor indicates that the cited data corruption is not a vulnerability in any existing use case; the length validation was added solely for robustness in the face of anomalous host OS behavior.
(CVE-2021-38160)

- fs/nfs/nfs4client.c in the Linux kernel before 5.13.4 has incorrect connection-setup ordering, which allows operators of remote NFSv4 servers to cause a denial of service (hanging of mounts) by arranging for those servers to be unreachable during trunking detection. (CVE-2021-38199)

- net/sunrpc/xdr.c in the Linux kernel before 5.13.4 allows remote attackers to cause a denial of service (xdr_set_page_base slab-out-of-bounds access) by performing many NFS 4.2 READ_PLUS operations.
(CVE-2021-38201)

- drivers/usb/host/max3421-hcd.c in the Linux kernel before 5.13.6 allows physically proximate attackers to cause a denial of service (use-after-free and panic) by removing a MAX-3421 USB device in certain situations. (CVE-2021-38204)

- drivers/net/ethernet/xilinx/xilinx_emaclite.c in the Linux kernel before 5.13.3 makes it easier for attackers to defeat an ASLR protection mechanism because it prints a kernel pointer (i.e., the real IOMEM pointer). (CVE-2021-38205)

- loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation. (CVE-2021-41073)

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-5092-1

Plugin Details

Severity: High

ID: 153770

File Name: ubuntu_USN-5092-1.nasl

Version: 1.2

Type: local

Agent: unix

Published: 9/28/2021

Updated: 9/28/2021

Supported Sensors: Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent

Risk Information

CVSS Score Source: CVE-2021-38160

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

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

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

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

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-aws, p-cpe:/a:canonical:ubuntu_linux:linux-aws-5.11-cloud-tools-5.11.0-1019, p-cpe:/a:canonical:ubuntu_linux:linux-aws-5.11-headers-5.11.0-1019, p-cpe:/a:canonical:ubuntu_linux:linux-aws-5.11-tools-5.11.0-1019, p-cpe:/a:canonical:ubuntu_linux:linux-aws-edge, p-cpe:/a:canonical:ubuntu_linux:linux-buildinfo-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-cloud-tools-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-headers-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-headers-aws, p-cpe:/a:canonical:ubuntu_linux:linux-headers-aws-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws-edge, p-cpe:/a:canonical:ubuntu_linux:linux-modules-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-modules-extra-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-modules-extra-aws, p-cpe:/a:canonical:ubuntu_linux:linux-modules-extra-aws-edge, p-cpe:/a:canonical:ubuntu_linux:linux-tools-5.11.0-1019-aws, p-cpe:/a:canonical:ubuntu_linux:linux-tools-aws, p-cpe:/a:canonical:ubuntu_linux:linux-tools-aws-edge

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

Exploit Ease: No known exploits are available

Patch Publication Date: 9/28/2021

Vulnerability Publication Date: 6/23/2021

Reference Information

CVE: CVE-2021-3679, CVE-2021-33624, CVE-2021-34556, CVE-2021-35477, CVE-2021-37159, CVE-2021-37576, CVE-2021-38160, CVE-2021-38199, CVE-2021-38201, CVE-2021-38204, CVE-2021-38205, CVE-2021-41073

USN: 5092-1