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High ALAS2-2021-1719 19 CVEs

Important: kernel security update (Amazon Linux 2)

Published Oct 28, 2021 · Updated May 19, 2025

Ecosystem: Amazon Linux

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2021-47497: In the Linux kernel, the following vulnerability has been resolved: nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells CVE-2021-47434: In the Linux kernel, the following vulnerability has been resolved: xhci: Fix command ring pointer corruption while aborting a command CVE-2021-47425: In the Linux kernel, the following vulnerability has been resolved: i2c: acpi: fix resource leak in reconfiguration device addition CVE-2021-47418: In the Linux kernel, the following vulnerability has been resolved: net_sched: fix NULL deref in fifo_set_limit() CVE-2021-47416: In the Linux kernel, the following vulnerability has been resolved: phy: mdio: fix memory leak CVE-2021-47405: In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: free raw_report buffers in usbhid_stop CVE-2021-47404: In the Linux kernel, the following vulnerability has been resolved: HID: betop: fix slab-out-of-bounds Write in betop_probe CVE-2021-47397: In the Linux kernel, the following vulnerability has been resolved: sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb CVE-2021-47387: In the Linux kernel, the following vulnerability has been resolved: cpufreq: schedutil: Use kobject release() method to free sugov_tunables CVE-2021-47383: In the Linux kernel, the following vulnerability has been resolved: tty: Fix out-of-bound vmalloc access in imageblit CVE-2021-47375: In the Linux kernel, the following vulnerability has been resolved: blktrace: Fix uaf in blk_trace access after removing by sysfs CVE-2021-47373: In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v3-its: Fix potential VPE leak on error CVE-2021-41864: An out-of-bounds (OOB) memory write flaw was found in prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the bpf in the Linux kernel. In this flaw, the multiplication to calculate the size could lead to an integer overflow which could allow a local attacker, with a special user privilege, to gain access to out-of-bounds memory leading to a system crash or a leak of internal kernel information. CVE-2021-38300: A flaw was found in the Linux kernel. The cBPF JIT compiler may produce machine code with incorrect branches. This flaw allows an unprivileged user to craft anomalous machine code, where the control flow is hijacked to execute arbitrary kernel code. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability. CVE-2021-3764: A memory leak flaw was found in the Linux kernel's ccp_run_aes_gcm_cmd() function that allows an attacker to cause a denial of service. The vulnerability is similar to the older CVE-2019-18808. The highest threat from this vulnerability is to system availability. CVE-2021-3744: A flaw was found in the Linux kernel. A memory leak in the ccp-ops crypto driver can allow attackers to cause a denial of service. This vulnerability is similar with the older CVE-2019-18808. The highest threat from this vulnerability is to system availability. CVE-2021-37159: A flaw use-after-free in the Linux kernel USB High Speed Mobile Devices functionality was found in the way user detaches USB device. A local user could use this flaw to crash the system or escalate their privileges on the system. CVE-2021-20321: A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system. CVE-2021-20317: A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP. The highest threat from this vulnerability is system availability.

Fixed packages 14

ReleasePackageFixed in
Amazon Linux · 2 kernel 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-debuginfo 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-debuginfo-common-aarch64 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-debuginfo-common-x86_64 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-devel 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-headers 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-livepatch-4.14.252-195.481 0:1.0-0.amzn2
Amazon Linux · 2 kernel-tools 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-tools-debuginfo 0:4.14.252-195.481.amzn2
Amazon Linux · 2 kernel-tools-devel 0:4.14.252-195.481.amzn2
Amazon Linux · 2 perf 0:4.14.252-195.481.amzn2
Amazon Linux · 2 perf-debuginfo 0:4.14.252-195.481.amzn2
Amazon Linux · 2 python-perf 0:4.14.252-195.481.amzn2
Amazon Linux · 2 python-perf-debuginfo 0:4.14.252-195.481.amzn2

Vulnerabilities 19

  • High 7.8
    CVE-2021-47383

    tty: Fix out-of-bound vmalloc access in imageblit

    In the Linux kernel, the following vulnerability has been resolved: tty: Fix out-of-bound vmalloc access in imageblit This issue happens when a userspace program does an ioctl FBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct containing only the fields…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • High 7.5
    CVE-2021-47397

    sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb

    In the Linux kernel, the following vulnerability has been resolved: sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb We should always check if skb_header_pointer's return is NULL before using it, otherwise it may cause null-ptr-deref, as sy…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Medium 6.2
    CVE-2021-47375

    blktrace: Fix uaf in blk_trace access after removing by sysfs

    In the Linux kernel, the following vulnerability has been resolved: blktrace: Fix uaf in blk_trace access after removing by sysfs There is an use-after-free problem triggered by following process: P1(sda) P2(sdb) echo 0 > /sys/block/sdb/trace/enable blk_trace…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-20317

    A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add…

    linux-raspi2 linux-hwe linux-azure linux-riscv Debian Ubuntu
  • Unscored —
    CVE-2021-20321

    A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in …

    linux-raspi2 linux-hwe linux-azure linux-riscv Debian Ubuntu
  • Unscored —
    CVE-2021-37159

    hso_free_net_device in drivers/net/usb/hso.c in the Linux kernel through 5.13.4 calls unregister_netdev without checkin…

    linux-raspi2 linux-hwe linux-azure linux-riscv Debian Ubuntu Azure Linux
  • Unscored —
    CVE-2021-3744

    A memory leak flaw was found in the Linux kernel in the ccp_run_aes_gcm_cmd() function in drivers/crypto/ccp/ccp-ops.c,…

    linux-raspi2 linux-hwe linux-azure linux-riscv Debian Ubuntu
  • Unscored —
    CVE-2021-3764

    A memory leak flaw was found in the Linux kernel's ccp_run_aes_gcm_cmd() function that allows an attacker to cause a de…

    linux-raspi2 linux-hwe linux-azure linux-riscv Linux Debian Ubuntu
  • Unscored —
    CVE-2021-38300

    arch/mips/net/bpf_jit.c in the Linux kernel before 5.4.10 can generate undesirable machine code when transforming unpri…

    linux linux-realtime linux-raspi-realtime linux-intel-iot-realtime Debian Ubuntu Azure Linux
  • Unscored —
    CVE-2021-41864

    prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel before 5.14.12 allows unprivileged users to tr…

    linux-raspi2 linux-hwe linux-azure linux-riscv Debian Ubuntu Azure Linux
  • Unscored —
    CVE-2021-47373

    irqchip/gic-v3-its: Fix potential VPE leak on error

    In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v3-its: Fix potential VPE leak on error In its_vpe_irq_domain_alloc, when its_vpe_init() returns an error, there is an off-by-one in the number of VPEs to be freed. Fix it by simp…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47387

    cpufreq: schedutil: Use kobject release() method to free sugov_tunables

    In the Linux kernel, the following vulnerability has been resolved: cpufreq: schedutil: Use kobject release() method to free sugov_tunables The struct sugov_tunables is protected by the kobject, so we can't free it directly. Otherwise we would get a call trac…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47404

    HID: betop: fix slab-out-of-bounds Write in betop_probe

    In the Linux kernel, the following vulnerability has been resolved: HID: betop: fix slab-out-of-bounds Write in betop_probe Syzbot reported slab-out-of-bounds Write bug in hid-betopff driver. The problem is the driver assumes the device must have an input rep…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47405

    HID: usbhid: free raw_report buffers in usbhid_stop

    In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: free raw_report buffers in usbhid_stop Free the unsent raw_report buffers when the device is removed. Fixes a memory leak reported by syzbot at: https://syzkaller.appspot.com/bug…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47416

    phy: mdio: fix memory leak

    In the Linux kernel, the following vulnerability has been resolved: phy: mdio: fix memory leak Syzbot reported memory leak in MDIO bus interface, the problem was in wrong state logic. MDIOBUS_ALLOCATED indicates 2 states: 1. Bus is only allocated 2. Bus alloc…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47418

    net_sched: fix NULL deref in fifo_set_limit()

    In the Linux kernel, the following vulnerability has been resolved: net_sched: fix NULL deref in fifo_set_limit() syzbot reported another NULL deref in fifo_set_limit() [1] I could repro the issue with : unshare -n tc qd add dev lo root handle 1:0 tbf limit 2…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47425

    i2c: acpi: fix resource leak in reconfiguration device addition

    In the Linux kernel, the following vulnerability has been resolved: i2c: acpi: fix resource leak in reconfiguration device addition acpi_i2c_find_adapter_by_handle() calls bus_find_device() which takes a reference on the adapter which is never released which …

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47434

    xhci: Fix command ring pointer corruption while aborting a command

    In the Linux kernel, the following vulnerability has been resolved: xhci: Fix command ring pointer corruption while aborting a command The command ring pointer is located at [6:63] bits of the command ring control register (CRCR). All the control bits like co…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2021-47497

    nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells

    In the Linux kernel, the following vulnerability has been resolved: nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); will become …

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-20317.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-20321.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-37159.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-3744.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-3764.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-38300.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-41864.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47373.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47375.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47383.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47387.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47397.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47404.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47405.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47416.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47418.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47425.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47434.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-47497.html