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Unscored CVE-2021-47353 EUVD-2021-34358GHSA-v5r4-g8jp-rvxf

udf: Fix NULL pointer dereference in udf_symlink function

Published May 21, 2024 · Updated May 11, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: linux Package: linux Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.4 Package: linux-aws-5.8 Package: linux-aws-6.2 Package: linux-aws-fips Package: linux-aws-hwe Package: linux-azure Package: linux-azure-4.15 Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.4 Package: linux-azure-5.8 Package: linux-azure-6.2 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.2 Package: linux-azure-fips Package: linux-bluefield Package: linux-fips Package: linux-gcp Package: linux-gcp-4.15 Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.4 Package: linux-gcp-5.8 Package: linux-gcp-6.2 Package: linux-gcp-fips Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.19 Package: linux-hwe-5.4 Package: linux-hwe-5.8 Package: linux-hwe-6.2 Package: linux-hwe-edge Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-kvm Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.2 Package: linux-lts-xenial Package: linux-nvidia-6.2 Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.3 Package: linux-oracle-5.4 Package: linux-oracle-5.8 Package: linux-raspi Package: linux-raspi-5.4 Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-vmware Platform: Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

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

udf: Fix NULL pointer dereference in udf_symlink function

In function udf_symlink, epos.bh is assigned with the value returned
by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c
and returns the value of sb_getblk function that could be NULL.
Then, epos.bh is used without any check, causing a possible
NULL pointer dereference when sb_getblk fails.

This fix adds a check to validate the value of epos.bh.

Affected products

VendorProductAffectedFixed
Linux Linux 2.6.12 4.4.276

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 linux 5.14.6-1 —
Debian 13 linux 5.14.6-1 —
Debian 12 linux 5.14.6-1 —
ReleasePackageFixed inAdvisory
Ubuntu 24.04 LTS linux-raspi-realtime No fix yet —
Ubuntu 22.04 LTS linux-riscv +22 No fix yet —
Ubuntu 20.04 LTS linux 5.4.0-84.94 —
Ubuntu 20.04 LTS linux-aws 5.4.0-1056.59 —
Ubuntu 20.04 LTS linux-azure 5.4.0-1058.60 —
Ubuntu 20.04 LTS linux-bluefield 5.4.0-1019.22 —
Ubuntu 20.04 LTS linux-gcp 5.4.0-1052.56 —
Ubuntu 20.04 LTS linux-gke +26 No fix yet —
Ubuntu 20.04 LTS linux-gkeop 5.4.0-1023.24 —
Ubuntu 20.04 LTS linux-kvm 5.4.0-1046.48 —
Ubuntu 20.04 LTS linux-oracle 5.4.0-1054.58 —
Ubuntu 20.04 LTS linux-raspi 5.4.0-1043.47 —
Ubuntu 18.04 LTS linux 4.15.0-156.163 —
Ubuntu 18.04 LTS linux-aws 4.15.0-1111.118 —
Ubuntu 18.04 LTS linux-aws-5.4 5.4.0-1056.59~18.04.1 —
Ubuntu 18.04 LTS linux-azure-4.15 4.15.0-1123.136 —
Ubuntu 18.04 LTS linux-azure-5.4 5.4.0-1058.60~18.04.1 —
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Ubuntu 18.04 LTS linux-gcp-4.15 4.15.0-1108.122 —
Ubuntu 18.04 LTS linux-gcp-5.4 5.4.0-1052.56~18.04.1 —
Ubuntu 18.04 LTS linux-hwe-5.4 5.4.0-84.94~18.04.1 —
Ubuntu 18.04 LTS linux-kvm 4.15.0-1099.101 —
Ubuntu 18.04 LTS linux-oracle 4.15.0-1080.88 —
Ubuntu 18.04 LTS linux-oracle-5.4 5.4.0-1054.58~18.04.1 —
Ubuntu 18.04 LTS linux-raspi-5.4 5.4.0-1043.47~18.04.1 —
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Show 8 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu Pro FIPS 20.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro FIPS 18.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro FIPS 16.04 LTS linux-fips No fix yet —
Ubuntu Pro FIPS-updates 20.04 LTS linux-aws-fips 5.4.0-1069.73+fips2 —
Ubuntu Pro FIPS-updates 20.04 LTS linux-azure-fips 5.4.0-1073.76+fips1 —
Ubuntu Pro FIPS-updates 20.04 LTS linux-fips 5.4.0-1033.38 —
Ubuntu Pro FIPS-updates 20.04 LTS linux-gcp-fips 5.4.0-1067.71~20.04.1 —
Ubuntu Pro FIPS-updates 18.04 LTS linux-aws-fips 4.15.0-2053.55 —
Ubuntu Pro FIPS-updates 18.04 LTS linux-azure-fips 4.15.0-2035.39 —
Ubuntu Pro FIPS-updates 18.04 LTS linux-fips 4.15.0-1069.78 —
Ubuntu Pro FIPS-updates 18.04 LTS linux-gcp-fips 4.15.0-2018.20 —
Ubuntu Pro FIPS-updates 16.04 LTS linux-fips 4.4.0-1114.121 USN-7554-3
Ubuntu Pro 16.04 LTS linux 4.4.0-269.303 USN-7554-1
Ubuntu Pro 16.04 LTS linux-aws 4.4.0-1182.197 USN-7554-1
Ubuntu Pro 16.04 LTS linux-aws-hwe 4.15.0-1111.118~16.04.1 —
Ubuntu Pro 16.04 LTS linux-azure 4.15.0-1123.136~16.04.1 —
Ubuntu Pro 16.04 LTS linux-gcp 4.15.0-1108.122~16.04.1 —
Ubuntu Pro 16.04 LTS linux-hwe 4.15.0-156.163~16.04.1 —
Ubuntu Pro 16.04 LTS linux-kvm 4.4.0-1145.156 USN-7554-1
Ubuntu Pro 16.04 LTS linux-oracle 4.15.0-1080.88~16.04.1 —
Ubuntu Pro 14.04 LTS linux No fix yet —
Ubuntu Pro 14.04 LTS linux-aws 4.4.0-1144.150 USN-7554-2
Ubuntu Pro 14.04 LTS linux-azure 4.15.0-1123.136~14.04.1 —
Ubuntu Pro 14.04 LTS linux-lts-xenial 4.4.0-269.303~14.04.1 USN-7554-2
ReleasePackageFixed inAdvisory
RHEL 8 kernel-rt +12 4.18.0-553.8.1.rt7.349.el8_10 RHSA-2024:4352
RHEL 8 perf +26 4.18.0-553.8.1.el8_10 RHSA-2024:4211

AlmaLinux

Errata ↗
ReleasePackageFixed inAdvisory
AlmaLinux 8 kernel-rt +11 4.18.0-553.8.1.rt7.349.el8_10 ALSA-2024:4352
AlmaLinux 8 perf +24 4.18.0-553.8.1.el8_10 ALSA-2024:4211

Rocky Linux

Errata ↗
ReleasePackageFixed inAdvisory
Rocky Linux 8 kernel 4.18.0-553.8.1.el8_10 RLSA-2024:4211
Rocky Linux 8 kernel-rt 4.18.0-553.8.1.rt7.349.el8_10 RLSA-2024:4352
ReleasePackageFixed inAdvisory
SLES 15 SP3 kernel-64kb +7 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLES 15 SP3 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1
SLES 12 SP5 kernel-azure +2 4.12.14-16.188.1 SUSE-SU-2024:1979-1
SLES 12 SP5 kernel-docs +4 4.12.14-122.219.1 SUSE-SU-2024:2184-1
Show 9 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 15 SP3 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1
SLES for SAP 15 SP3 kernel-docs +5 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLES for SAP 12 SP5 kernel-azure +2 4.12.14-16.188.1 SUSE-SU-2024:1979-1
SLES for SAP 12 SP5 kernel-syms +2 4.12.14-122.219.1 SUSE-SU-2024:2184-1
SLE Real Time 12 SP5 kernel-rt +3 4.12.14-10.188.1 SUSE-SU-2024:1983-1
SLE Micro 5.2 kernel-default 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLE Micro 5.2 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1
SLE Micro 5.2 kernel-rt +1 5.3.18-150300.172.1 SUSE-SU-2024:2010-1
SLE Micro 5.1 kernel-default 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLE Micro 5.1 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1
SLE Micro 5.1 kernel-rt +1 5.3.18-150300.172.1 SUSE-SU-2024:2010-1
SLE Live Patching 15 SP3 kernel-default 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLE Live Patching 15 SP3 kernel-livepatch-SLE15-SP3_Update_45 1-150300.7.3.1 SUSE-SU-2024:2185-1
SLE Live Patching 12 SP5 kernel-default 4.12.14-122.219.1 SUSE-SU-2024:2184-1
SLE Live Patching 12 SP5 kgraft-patch-SLE12-SP5_Update_57 1-8.3.1 SUSE-SU-2024:2184-1
SLE HPC 15 SP3 kernel-64kb +6 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SLE HPC 15 SP3 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1
SUSE Enterprise Storage 7.1 kernel-64kb +6 5.3.18-150300.59.164.1 SUSE-SU-2024:2185-1
SUSE Enterprise Storage 7.1 kernel-default-base 5.3.18-150300.59.164.1.150300.18.96.1 SUSE-SU-2024:2185-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2 kernel-livepatch-4.14.241-184.433 1.0-0.amzn2 ALAS2-2021-1696
Amazon Linux 2 perf +8 4.14.241-184.433.amzn2 ALAS2-2021-1696

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 8 perf +19 4.18.0-553.8.1.el8_10 ELSA-2024-4211
Oracle Linux 7 kernel-uek +5 4.1.12-124.89.4.el7uek ELSA-2024-12606

Advisories 18

References