Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-47356

Use After Free

Published: May 21, 2024 | Modified: Apr 02, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
6.7 MODERATE
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM
Vulnerability-free packages from our partners
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-47356
CWEhttps://cwe.mitre.org/data/definitions/416.html

In the Linux kernel, the following vulnerability has been resolved:

mISDN: fix possible use-after-free in HFC_cleanup()

This modules remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the drivers remove function has finished, which would result in a use-after-free.

Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

NameVendorStart VersionEnd Version
Linux_kernelLinux*4.4.276 (excluding)
Linux_kernelLinux4.5 (including)4.9.276 (excluding)
Linux_kernelLinux4.10 (including)4.14.240 (excluding)
Linux_kernelLinux4.15 (including)4.19.198 (excluding)
Linux_kernelLinux4.20 (including)5.4.133 (excluding)
Linux_kernelLinux5.5 (including)5.10.51 (excluding)
Linux_kernelLinux5.11 (including)5.12.18 (excluding)
Linux_kernelLinux5.13 (including)5.13.3 (excluding)
Red Hat Enterprise Linux 8RedHatkernel-rt-0:4.18.0-553.8.1.rt7.349.el8_10*
Red Hat Enterprise Linux 8RedHatkernel-0:4.18.0-553.8.1.el8_10*
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportRedHatkernel-0:4.18.0-372.119.1.el8_6*
Red Hat Enterprise Linux 8.6 Telecommunications Update ServiceRedHatkernel-0:4.18.0-372.119.1.el8_6*
Red Hat Enterprise Linux 8.6 Update Services for SAP SolutionsRedHatkernel-0:4.18.0-372.119.1.el8_6*
Red Hat Enterprise Linux 8.8 Extended Update SupportRedHatkernel-0:4.18.0-477.74.1.el8_8*
LinuxUbuntubionic*
LinuxUbuntuesm-infra-legacy/trusty*
LinuxUbuntuesm-infra/bionic*
LinuxUbuntuesm-infra/focal*
LinuxUbuntuesm-infra/xenial*
LinuxUbuntufocal*
LinuxUbuntutrusty*
LinuxUbuntutrusty/esm*
LinuxUbuntuupstream*
LinuxUbuntuxenial*
Linux-allwinner-5.19Ubuntujammy*
Linux-allwinner-5.19Ubuntuupstream*
Linux-awsUbuntubionic*
Linux-awsUbuntuesm-infra-legacy/trusty*
Linux-awsUbuntuesm-infra/bionic*
Linux-awsUbuntuesm-infra/focal*
Linux-awsUbuntuesm-infra/xenial*
Linux-awsUbuntufocal*
Linux-awsUbuntutrusty*
Linux-awsUbuntutrusty/esm*
Linux-awsUbuntuupstream*
Linux-awsUbuntuxenial*
Linux-aws-5.0Ubuntubionic*
Linux-aws-5.0Ubuntuesm-infra/bionic*
Linux-aws-5.0Ubuntuupstream*
Linux-aws-5.11Ubuntuesm-infra/focal*
Linux-aws-5.11Ubuntufocal*
Linux-aws-5.11Ubuntuupstream*
Linux-aws-5.13Ubuntuesm-infra/focal*
Linux-aws-5.13Ubuntufocal*
Linux-aws-5.13Ubuntuupstream*
Linux-aws-5.15Ubuntuupstream*
Linux-aws-5.19Ubuntujammy*
Linux-aws-5.19Ubuntuupstream*
Linux-aws-5.3Ubuntubionic*
Linux-aws-5.3Ubuntuesm-infra/bionic*
Linux-aws-5.3Ubuntuupstream*
Linux-aws-5.4Ubuntubionic*
Linux-aws-5.4Ubuntuesm-infra/bionic*
Linux-aws-5.4Ubuntuupstream*
Linux-aws-5.8Ubuntuesm-infra/focal*
Linux-aws-5.8Ubuntufocal*
Linux-aws-5.8Ubuntuupstream*
Linux-aws-6.14Ubuntuupstream*
Linux-aws-6.2Ubuntujammy*
Linux-aws-6.2Ubuntuupstream*
Linux-aws-6.5Ubuntuupstream*
Linux-aws-6.8Ubuntuupstream*
Linux-aws-fipsUbuntufips-updates/bionic*
Linux-aws-fipsUbuntufips-updates/focal*
Linux-aws-fipsUbuntufips/bionic*
Linux-aws-fipsUbuntufips/focal*
Linux-aws-fipsUbuntutrusty*
Linux-aws-fipsUbuntuupstream*
Linux-aws-fipsUbuntuxenial*
Linux-aws-hweUbuntuesm-infra/xenial*
Linux-aws-hweUbuntuupstream*
Linux-aws-hweUbuntuxenial*
Linux-azureUbuntubionic*
Linux-azureUbuntuesm-infra-legacy/trusty*
Linux-azureUbuntuesm-infra/bionic*
Linux-azureUbuntuesm-infra/focal*
Linux-azureUbuntuesm-infra/xenial*
Linux-azureUbuntufocal*
Linux-azureUbuntutrusty*
Linux-azureUbuntutrusty/esm*
Linux-azureUbuntuupstream*
Linux-azureUbuntuxenial*
Linux-azure-4.15Ubuntubionic*
Linux-azure-4.15Ubuntuesm-infra/bionic*
Linux-azure-4.15Ubuntuupstream*
Linux-azure-5.11Ubuntuesm-infra/focal*
Linux-azure-5.11Ubuntufocal*
Linux-azure-5.11Ubuntuupstream*
Linux-azure-5.13Ubuntuesm-infra/focal*
Linux-azure-5.13Ubuntufocal*
Linux-azure-5.13Ubuntuupstream*
Linux-azure-5.15Ubuntuupstream*
Linux-azure-5.19Ubuntujammy*
Linux-azure-5.19Ubuntuupstream*
Linux-azure-5.3Ubuntubionic*
Linux-azure-5.3Ubuntuesm-infra/bionic*
Linux-azure-5.3Ubuntuupstream*
Linux-azure-5.4Ubuntubionic*
Linux-azure-5.4Ubuntuesm-infra/bionic*
Linux-azure-5.4Ubuntuupstream*
Linux-azure-5.8Ubuntuesm-infra/focal*
Linux-azure-5.8Ubuntufocal*
Linux-azure-5.8Ubuntuupstream*
Linux-azure-6.11Ubuntuupstream*
Linux-azure-6.14Ubuntuupstream*
Linux-azure-6.2Ubuntujammy*
Linux-azure-6.2Ubuntuupstream*
Linux-azure-6.5Ubuntuupstream*
Linux-azure-6.8Ubuntuupstream*
Linux-azure-edgeUbuntubionic*
Linux-azure-edgeUbuntuesm-infra/bionic*
Linux-azure-edgeUbuntuupstream*
Linux-azure-fdeUbuntuesm-infra/focal*
Linux-azure-fdeUbuntufocal*
Linux-azure-fdeUbuntuupstream*
Linux-azure-fde-5.15Ubuntuesm-infra/focal*
Linux-azure-fde-5.15Ubuntufocal*
Linux-azure-fde-5.15Ubuntuupstream*
Linux-azure-fde-5.19Ubuntujammy*
Linux-azure-fde-5.19Ubuntuupstream*
Linux-azure-fde-6.14Ubuntuupstream*
Linux-azure-fde-6.2Ubuntujammy*
Linux-azure-fde-6.2Ubuntuupstream*
Linux-azure-fde-6.8Ubuntuupstream*
Linux-azure-fipsUbuntufips-updates/bionic*
Linux-azure-fipsUbuntufips-updates/focal*
Linux-azure-fipsUbuntufips/bionic*
Linux-azure-fipsUbuntufips/focal*
Linux-azure-fipsUbuntutrusty*
Linux-azure-fipsUbuntuupstream*
Linux-azure-fipsUbuntuxenial*
Linux-azure-nvidiaUbuntuupstream*
Linux-azure-nvidia-6.14Ubuntuupstream*
Linux-bluefieldUbuntuesm-infra/focal*
Linux-bluefieldUbuntufocal*
Linux-bluefieldUbuntuupstream*
Linux-fipsUbuntufips-updates/bionic*
Linux-fipsUbuntufips-updates/focal*
Linux-fipsUbuntufips-updates/xenial*
Linux-fipsUbuntufips/bionic*
Linux-fipsUbuntufips/focal*
Linux-fipsUbuntufips/xenial*
Linux-fipsUbuntuupstream*
Linux-gcpUbuntubionic*
Linux-gcpUbuntuesm-infra/bionic*
Linux-gcpUbuntuesm-infra/focal*
Linux-gcpUbuntuesm-infra/xenial*
Linux-gcpUbuntufocal*
Linux-gcpUbuntuupstream*
Linux-gcpUbuntuxenial*
Linux-gcp-4.15Ubuntubionic*
Linux-gcp-4.15Ubuntuesm-infra/bionic*
Linux-gcp-4.15Ubuntuupstream*
Linux-gcp-5.11Ubuntuesm-infra/focal*
Linux-gcp-5.11Ubuntufocal*
Linux-gcp-5.11Ubuntuupstream*
Linux-gcp-5.13Ubuntuesm-infra/focal*
Linux-gcp-5.13Ubuntufocal*
Linux-gcp-5.13Ubuntuupstream*
Linux-gcp-5.15Ubuntuupstream*
Linux-gcp-5.19Ubuntujammy*
Linux-gcp-5.19Ubuntuupstream*
Linux-gcp-5.3Ubuntubionic*
Linux-gcp-5.3Ubuntuesm-infra/bionic*
Linux-gcp-5.3Ubuntuupstream*
Linux-gcp-5.4Ubuntubionic*
Linux-gcp-5.4Ubuntuesm-infra/bionic*
Linux-gcp-5.4Ubuntuupstream*
Linux-gcp-5.8Ubuntuesm-infra/focal*
Linux-gcp-5.8Ubuntufocal*
Linux-gcp-5.8Ubuntuupstream*
Linux-gcp-6.11Ubuntuupstream*
Linux-gcp-6.14Ubuntuupstream*
Linux-gcp-6.2Ubuntujammy*
Linux-gcp-6.2Ubuntuupstream*
Linux-gcp-6.5Ubuntuupstream*
Linux-gcp-6.8Ubuntuupstream*
Linux-gcp-fipsUbuntufips-updates/bionic*
Linux-gcp-fipsUbuntufips-updates/focal*
Linux-gcp-fipsUbuntufips/bionic*
Linux-gcp-fipsUbuntufips/focal*
Linux-gcp-fipsUbuntutrusty*
Linux-gcp-fipsUbuntuupstream*
Linux-gcp-fipsUbuntuxenial*
Linux-gkeUbuntuesm-infra/focal*
Linux-gkeUbuntufocal*
Linux-gkeUbuntuupstream*
Linux-gkeUbuntuxenial*
Linux-gke-4.15Ubuntubionic*
Linux-gke-4.15Ubuntuesm-infra/bionic*
Linux-gke-4.15Ubuntuupstream*
Linux-gke-5.15Ubuntuesm-infra/focal*
Linux-gke-5.15Ubuntufocal*
Linux-gke-5.15Ubuntuupstream*
Linux-gke-5.4Ubuntubionic*
Linux-gke-5.4Ubuntuesm-infra/bionic*
Linux-gke-5.4Ubuntuupstream*
Linux-gkeopUbuntuesm-infra/focal*
Linux-gkeopUbuntufocal*
Linux-gkeopUbuntuupstream*
Linux-gkeop-5.15Ubuntuupstream*
Linux-gkeop-5.4Ubuntubionic*
Linux-gkeop-5.4Ubuntuesm-infra/bionic*
Linux-gkeop-5.4Ubuntuupstream*
Linux-hweUbuntubionic*
Linux-hweUbuntuesm-infra/bionic*
Linux-hweUbuntuesm-infra/xenial*
Linux-hweUbuntuupstream*
Linux-hweUbuntuxenial*
Linux-hwe-5.11Ubuntuesm-infra/focal*
Linux-hwe-5.11Ubuntufocal*
Linux-hwe-5.11Ubuntuupstream*
Linux-hwe-5.13Ubuntuesm-infra/focal*
Linux-hwe-5.13Ubuntufocal*
Linux-hwe-5.13Ubuntuupstream*
Linux-hwe-5.15Ubuntuupstream*
Linux-hwe-5.19Ubuntujammy*
Linux-hwe-5.19Ubuntuupstream*
Linux-hwe-5.4Ubuntubionic*
Linux-hwe-5.4Ubuntuesm-infra/bionic*
Linux-hwe-5.4Ubuntuupstream*
Linux-hwe-5.8Ubuntuesm-infra/focal*
Linux-hwe-5.8Ubuntufocal*
Linux-hwe-5.8Ubuntuupstream*
Linux-hwe-6.11Ubuntuupstream*
Linux-hwe-6.14Ubuntuupstream*
Linux-hwe-6.2Ubuntujammy*
Linux-hwe-6.2Ubuntuupstream*
Linux-hwe-6.5Ubuntuupstream*
Linux-hwe-6.8Ubuntuupstream*
Linux-hwe-edgeUbuntubionic*
Linux-hwe-edgeUbuntuesm-infra/bionic*
Linux-hwe-edgeUbuntuesm-infra/xenial*
Linux-hwe-edgeUbuntuupstream*
Linux-hwe-edgeUbuntuxenial*
Linux-ibmUbuntumantic*
Linux-ibmUbuntuupstream*
Linux-ibm-5.15Ubuntuupstream*
Linux-ibm-5.4Ubuntuupstream*
Linux-ibm-6.8Ubuntuupstream*
Linux-intelUbuntuupstream*
Linux-intel-5.13Ubuntuesm-infra/focal*
Linux-intel-5.13Ubuntufocal*
Linux-intel-5.13Ubuntuupstream*
Linux-intel-iot-realtimeUbuntujammy*
Linux-intel-iot-realtimeUbuntuupstream*
Linux-intel-iotgUbuntuupstream*
Linux-intel-iotg-5.15Ubuntuupstream*
Linux-iotUbuntuupstream*
Linux-kvmUbuntubionic*
Linux-kvmUbuntuesm-infra/bionic*
Linux-kvmUbuntuesm-infra/focal*
Linux-kvmUbuntuesm-infra/xenial*
Linux-kvmUbuntufocal*
Linux-kvmUbuntuupstream*
Linux-kvmUbuntuxenial*
Linux-laptopUbuntuupstream*
Linux-lowlatencyUbuntuupstream*
Linux-lowlatency-hwe-5.15Ubuntuupstream*
Linux-lowlatency-hwe-5.19Ubuntujammy*
Linux-lowlatency-hwe-5.19Ubuntuupstream*
Linux-lowlatency-hwe-6.11Ubuntuupstream*
Linux-lowlatency-hwe-6.2Ubuntujammy*
Linux-lowlatency-hwe-6.2Ubuntuupstream*
Linux-lowlatency-hwe-6.5Ubuntuupstream*
Linux-lowlatency-hwe-6.8Ubuntuupstream*
Linux-lts-xenialUbuntuesm-infra-legacy/trusty*
Linux-lts-xenialUbuntutrusty*
Linux-lts-xenialUbuntutrusty/esm*
Linux-lts-xenialUbuntuupstream*
Linux-nvidiaUbuntuupstream*
Linux-nvidia-6.11Ubuntuupstream*
Linux-nvidia-6.2Ubuntujammy*
Linux-nvidia-6.2Ubuntuupstream*
Linux-nvidia-6.5Ubuntuupstream*
Linux-nvidia-6.8Ubuntuupstream*
Linux-nvidia-lowlatencyUbuntuupstream*
Linux-nvidia-tegraUbuntuupstream*
Linux-nvidia-tegra-5.15Ubuntuupstream*
Linux-nvidia-tegra-igxUbuntuupstream*
Linux-oemUbuntubionic*
Linux-oemUbuntuesm-infra/bionic*
Linux-oemUbuntuupstream*
Linux-oemUbuntuxenial*
Linux-oem-5.10Ubuntuesm-infra/focal*
Linux-oem-5.10Ubuntufocal*
Linux-oem-5.10Ubuntuupstream*
Linux-oem-5.13Ubuntuesm-infra/focal*
Linux-oem-5.13Ubuntufocal*
Linux-oem-5.13Ubuntuupstream*
Linux-oem-5.14Ubuntuesm-infra/focal*
Linux-oem-5.14Ubuntufocal*
Linux-oem-5.14Ubuntuupstream*
Linux-oem-5.17Ubuntujammy*
Linux-oem-5.17Ubuntuupstream*
Linux-oem-5.6Ubuntuesm-infra/focal*
Linux-oem-5.6Ubuntufocal*
Linux-oem-5.6Ubuntuupstream*
Linux-oem-6.0Ubuntujammy*
Linux-oem-6.0Ubuntuupstream*
Linux-oem-6.1Ubuntujammy*
Linux-oem-6.1Ubuntuupstream*
Linux-oem-6.11Ubuntuupstream*
Linux-oem-6.14Ubuntuupstream*
Linux-oem-6.17Ubuntuupstream*
Linux-oem-6.5Ubuntuupstream*
Linux-oem-6.8Ubuntuupstream*
Linux-oracleUbuntubionic*
Linux-oracleUbuntuesm-infra/bionic*
Linux-oracleUbuntuesm-infra/focal*
Linux-oracleUbuntuesm-infra/xenial*
Linux-oracleUbuntufocal*
Linux-oracleUbuntuupstream*
Linux-oracleUbuntuxenial*
Linux-oracle-5.0Ubuntubionic*
Linux-oracle-5.0Ubuntuesm-infra/bionic*
Linux-oracle-5.0Ubuntuupstream*
Linux-oracle-5.11Ubuntuesm-infra/focal*
Linux-oracle-5.11Ubuntufocal*
Linux-oracle-5.11Ubuntuupstream*
Linux-oracle-5.13Ubuntuesm-infra/focal*
Linux-oracle-5.13Ubuntufocal*
Linux-oracle-5.13Ubuntuupstream*
Linux-oracle-5.15Ubuntuupstream*
Linux-oracle-5.3Ubuntubionic*
Linux-oracle-5.3Ubuntuesm-infra/bionic*
Linux-oracle-5.3Ubuntuupstream*
Linux-oracle-5.4Ubuntubionic*
Linux-oracle-5.4Ubuntuesm-infra/bionic*
Linux-oracle-5.4Ubuntuupstream*
Linux-oracle-5.8Ubuntuesm-infra/focal*
Linux-oracle-5.8Ubuntufocal*
Linux-oracle-5.8Ubuntuupstream*
Linux-oracle-6.14Ubuntuupstream*
Linux-oracle-6.5Ubuntuupstream*
Linux-oracle-6.8Ubuntuupstream*
Linux-raspiUbuntuesm-infra/focal*
Linux-raspiUbuntufocal*
Linux-raspiUbuntuupstream*
Linux-raspi-5.4Ubuntubionic*
Linux-raspi-5.4Ubuntuesm-infra/bionic*
Linux-raspi-5.4Ubuntuupstream*
Linux-raspi-realtimeUbuntunoble*
Linux-raspi-realtimeUbuntuupstream*
Linux-raspi2Ubuntubionic*
Linux-raspi2Ubuntuesm-infra/focal*
Linux-raspi2Ubuntufocal*
Linux-raspi2Ubuntuupstream*
Linux-raspi2Ubuntuxenial*
Linux-realtimeUbuntujammy*
Linux-realtimeUbuntuupstream*
Linux-realtime-6.14Ubuntuupstream*
Linux-realtime-6.8Ubuntuupstream*
Linux-riscvUbuntuesm-infra/focal*
Linux-riscvUbuntufocal*
Linux-riscvUbuntujammy*
Linux-riscvUbuntuupstream*
Linux-riscv-5.11Ubuntuesm-infra/focal*
Linux-riscv-5.11Ubuntufocal*
Linux-riscv-5.11Ubuntuupstream*
Linux-riscv-5.15Ubuntuupstream*
Linux-riscv-5.19Ubuntujammy*
Linux-riscv-5.19Ubuntuupstream*
Linux-riscv-5.8Ubuntuesm-infra/focal*
Linux-riscv-5.8Ubuntufocal*
Linux-riscv-5.8Ubuntuupstream*
Linux-riscv-6.14Ubuntuupstream*
Linux-riscv-6.5Ubuntuupstream*
Linux-riscv-6.8Ubuntuupstream*
Linux-starfiveUbuntuupstream*
Linux-starfive-5.19Ubuntujammy*
Linux-starfive-5.19Ubuntuupstream*
Linux-starfive-6.2Ubuntujammy*
Linux-starfive-6.2Ubuntuupstream*
Linux-starfive-6.5Ubuntuupstream*
Linux-xilinxUbuntuupstream*
Linux-xilinx-zynqmpUbuntuupstream*

Potential Mitigations

References

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