synced 5 MIN AGO
01 Record

CVE-2021-3543

A flaw null pointer dereference in the Nitro Enclaves kernel driver was found in the way that Enclaves VMs forces closures on the enclave file descriptor. A local user of a host machine could use this

UnratedPUBLISHEDCNA: redhat
CNA base scoreUnratedNo CNA CVSS vector
View raw JSON

02 Description

A flaw null pointer dereference in the Nitro Enclaves kernel driver was found in the way that Enclaves VMs forces closures on the enclave file descriptor. A local user of a host machine could use this

03 Exploitation and scoring

Exploitation
Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
SSVC decision
Not assessed by CISA
EPSS probability
0.30% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 22.6% of scored records. A rank, not a probability.
NVD base score
6.7 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD analysis status
Modified. NVD last modified this record on 2026-06-17.
Red Hat severity
Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2021-06-01 13:20Z5 YR AGO
Last updated
2024-08-03 17:01Z2 YR AGO
Reserved
2021-05-10
Assigning CNA
redhat
Record state
PUBLISHED
Severity
Not rated by the issuing CNA
CNA CVSS vector
Not published by the issuing CNA
Weaknesses
Data version
5.1
Document digest
71bd5493b999a9bfc249053eee9088171561c4d9ee3e80c1481f24f6cd7e6763

05 Affected products

VendorProductVersionsPlatforms
n/akernelkernel 4.18.0—

06 References

07 Fixed in

AlmaLinux 8

  • kernel-tools-libs-devel
    Fixed in 4.18.0-305.3.1.el8_4

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

Arch Linux

  • linux
    Fixed in 5.12.3.arch1-1
  • linux-hardened
    Fixed in 5.11.20.hardened1-1
  • linux-lts
    Fixed in 5.10.36-1
  • linux-zen
    Fixed in 5.12.3.zen1-1

Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.

CloudLinux 8

  • kernel-tools-libs-devel
    Fixed in 4.18.0-305.3.1.el8_4

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

Debian 12

  • linux
    Fixed in 5.10.38-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

  • linux
    Fixed in 5.10.38-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

  • linux
    Fixed in 5.10.38-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 16.04 LTS

  • linux-hwe-edge
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 18.04 LTS

  • linux-aws-5.0
    No fix yet
  • linux-aws-5.3
    No fix yet
  • linux-aws-5.4
    Fixed in 5.4.0-1064.67~18.04.1
  • linux-azure
    No fix yet
  • linux-azure-5.3
    No fix yet
  • linux-azure-edge
    No fix yet
  • linux-gcp
    No fix yet
  • linux-gcp-5.3
    No fix yet
  • linux-gcp-edge
    No fix yet
  • linux-gke-4.15
    No fix yet
  • linux-hwe
    No fix yet
  • linux-hwe-edge
    No fix yet
  • linux-oem
    No fix yet
  • linux-oracle-5.0
    No fix yet
  • linux-oracle-5.3
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 20.04 LTS

  • linux-aws
    Fixed in 5.4.0-1064.67
  • linux-aws-5.8
    No fix yet
  • linux-oem-5.10
    Fixed in 5.10.0-1032.33
  • linux-raspi2
    No fix yet
  • linux-riscv
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.