The remote Ubuntu 20.04 LTS host has a package installed that is 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)

  - The eBPF RINGBUF bpf_ringbuf_reserve() function in the Linux kernel did not check that the allocated size     was smaller than the ringbuf size, allowing an attacker to perform out-of-bounds writes within the kernel     and therefore, arbitrary code execution. This issue was fixed via commit 4b81ccebaeee (bpf, ringbuf: Deny     reserve of buffers larger than ringbuf) (v5.13-rc4) and backported to the stable kernels in v5.12.4,     v5.11.21, and v5.10.37. It was introduced via 457f44363a88 (bpf: Implement BPF ring buffer and verifier     support for it) (v5.8-rc1). (CVE-2021-3489)

  - The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the Linux kernel did not properly     update 32-bit bounds, which could be turned into out of bounds reads and writes in the Linux kernel and     therefore, arbitrary code execution. This issue was fixed via commit 049c4e13714e (bpf: Fix alu32 const     subreg bound tracking on bitwise operations) (v5.13-rc4) and backported to the stable kernels in v5.12.4,     v5.11.21, and v5.10.37. The AND/OR issues were introduced by commit 3f50f132d840 (bpf: Verifier, do     explicit ALU32 bounds tracking) (5.7-rc1) and the XOR variant was introduced by 2921c90d4718 (bpf:Fix a     verifier failure with xor) ( 5.10-rc1). (CVE-2021-3490)

  - The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the     PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem.
    This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was     addressed via commit d1f82808877b (io_uring: truncate lengths larger than MAX_RW_COUNT on provide     buffers) (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was     introduced in ddf0322db79c (io_uring: add IORING_OP_PROVIDE_BUFFERS) (v5.7-rc1). (CVE-2021-3491)

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

Detections

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

high Nessus Plugin ID 149411

Version 1.9

Version 1.8

Version 1.8

Version 1.7

Version 1.6

Version 1.5

Version 1.9 Jan 10, 2024, 8:45 AM Detection (updated detection logic) Plugin metadata Plugin Feed: 202401100845
Version 1.8 Oct 21, 2023, 5:06 AM Detection Plugin metadata Plugin Feed: 202310210506
Version 1.8 Jan 9, 2024, 6:56 PM Plugin metadata Detection (updated detection logic) Plugin Feed: 202401091856
Version 1.7 Jan 18, 2023, 9:01 AM Logic Changes (Added support for s390x) Plugin Feed: 202301180901
Version 1.6 Jan 17, 2023, 1:55 PM Exploit attributes ("Exploit framework core" set to "True") Plugin Feed: 202301171355
Version 1.5 Nov 7, 2022, 3:54 PM CVSS temporal metrics Exploit attributes Plugin Feed: 202211071554