CVE-2021-3492

Aliases:UBUNTU-CVE-2021-3492
Advisory lineage Upstream: 0 Downstream: 4
Modified
Published: 17 Apr 2021, 04:20
Last modified:17 Sept 2024, 03:54

Vulnerability Summary

Overall Risk (default)
medium
36/100
CVSS Score
8.8 HIGH
v3.1 (cve.org)
EPSS Score
1.54% LOW
2% probability -22.91%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

17 Apr 2021, 04:20
Published
Vulnerability first disclosed
17 Sept 2024, 03:54
Last Modified
Vulnerability information updated

Description

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.

CVSS Metrics

  • v3.1•HIGH•Score: 8.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • v2.0•HIGH•Score: 7.2AV:L/AC:L/Au:N/C:C/I:C/A:C

EPSS Trends

Current EPSS score: 1.54%• Percentile: 74%

Techniques & Countermeasures

  • CWE-401•Missing Release of Memory after Effective Lifetime

    The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

  • CWE-415•Double Free

    The product calls free() twice on the same memory address.

Affected Systems

  • canonical•ubuntu_linux

    < 18.04 | ≥ 18.04.1, < 20.04 | < 20.10

  • ubuntu•linux

    < 5.4.0-72.80

  • ubuntu•linux-aws

    < 5.4.0-1045.47

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.4

    < 5.4.0-1045.47~18.04.1

  • ubuntu•linux-aws-fips

    < 5.4.0-1069.73+fips2 | all

  • ubuntu•linux-azure

    all | < 5.4.0-1046.48

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.4

    < 5.4.0-1046.48~18.04.1

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fips

    < 5.4.0-1073.76+fips1 | all

  • ubuntu•linux-bluefield

    all

  • ubuntu•linux-gcp

    all | < 5.4.0-1042.45

  • ubuntu•linux-gcp-5.3

    all

  • ubuntu•linux-gcp-5.4

    < 5.4.0-1042.45~18.04.1

  • ubuntu•linux-gcp-edge

    all

  • ubuntu•linux-gcp-fips

    < 5.4.0-1067.71~20.04.1 | all

  • ubuntu•linux-gke

    < 5.4.0-1042.44

  • ubuntu•linux-gke-5.3

    < 5.3.0-1042.45

  • ubuntu•linux-gke-5.4

    < 5.4.0-1042.44~18.04.1

  • ubuntu•linux-gkeop

    < 5.4.0-1014.15

  • ubuntu•linux-gkeop-5.4

    < 5.4.0-1014.15~18.04.1

  • ubuntu•linux-hwe

    < 5.3.0-73.69

  • ubuntu•linux-hwe-5.4

    < 5.4.0-72.80~18.04.1

  • ubuntu•linux-hwe-5.8

    < 5.8.0-50.56~20.04.1

  • ubuntu•linux-hwe-edge

    all | all

  • ubuntu•linux-intel-iot-realtime

    all

  • ubuntu•linux-kvm

    < 5.4.0-1038.39

  • ubuntu•linux-oem-5.10

    < 5.10.0-1022.23

  • ubuntu•linux-oem-5.6

    < 5.6.0-1054.58

  • ubuntu•linux-oracle

    < 5.4.0-1043.46

  • ubuntu•linux-oracle-5.0

    all

  • ubuntu•linux-oracle-5.3

    all

  • ubuntu•linux-oracle-5.4

    < 5.4.0-1043.46~18.04.1

  • ubuntu•linux-raspi

    < 5.4.0-1034.37

  • ubuntu•linux-raspi-5.4

    < 5.4.0-1034.37~18.04.1

  • ubuntu•linux-raspi-realtime

    all

  • ubuntu•linux-raspi2

    all

  • ubuntu•linux-raspi2-5.3

    < 5.3.0-1039.41

  • ubuntu•linux-realtime

    all

  • ubuntu•linux-riscv-5.8

    < 5.8.0-22.24~20.04.1

  • ubuntu•linux_kernel

    ≥ 5.8 kernel, < 5.8.0-50.56 | ≥ 5.4 kernel, < 5.4.0-72.80

References (9)