QID 352871

Date Published: 2021-11-15

QID 352871: Amazon Linux Security Advisory for kernel : ALAS-2021-1539

a flaw was found in the linux kernel.
When reusing a socket with an attached dccps_hc_tx_ccid as a listener, the socket will be used after being released leading to denial of service (dos) or a potential code execution.
The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. (
( CVE-2020-16119) a flaw was found in the linux kernels kvm implementation, where improper handing of the vm_io|vm_pfnmap vmas in kvm bypasses ro checks and leads to pages being freed while still accessible by the vmm and guest.
This flaw allows users who can start and control a vm to read/write random pages of memory, resulting in local privilege escalation.
The highest threat from this vulnerability is to confidentiality, integrity, and system availability. (
( CVE-2021-22543) a flaw was found in the can bcm networking protocol in the linux kernel, where a local attacker can abuse a flaw in the can subsystem to corrupt memory, crash the system or escalate privileges. (
( CVE-2021-3609) a vulnerability was found in the linux kernel.
Missing size validations on inbound sctp packets may allow the kernel to read uninitialized memory. (
( CVE-2021-3655) a lack of cpu resources in the linux kernel tracing module functionality was found in the way users use the trace ring buffer in 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)

Allows unauthorized disclosure of information; allows unauthorized modification; allows disruption of service.

  • CVSS V3 rated as High - 7.8 severity.
  • CVSS V2 rated as High - 7.2 severity.
  • Solution
    Please refer to Amazon advisory: ALAS-2021-1539 for affected packages and patching details, or update with your package manager.
    Vendor References
    Software Advisories
    Advisory ID Software Component Link
    ALAS-2021-1539 Amazon Linux URL Logo alas.aws.amazon.com/ALAS-2021-1539.html