CVE-2021-21781
An information disclosure vulnerability exists in the ARM SIGPAGE functionality of Linux Kernel v5.4.66 and v5.4.54. The latest version (5.11-rc4) seems to still be vulnerable. A userland application
02 Description
An information disclosure vulnerability exists in the ARM SIGPAGE functionality of Linux Kernel v5.4.66 and v5.4.54. The latest version (5.11-rc4) seems to still be vulnerable. A userland application
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
- 0.49% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 42.2% of scored records. A rank, not a probability.
- NVD base score
- 3.3 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- 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
- 2021-08-18 14:37Z5 YR AGO
- Last updated
- 2024-08-03 18:23Z2 YR AGO
- Reserved
- 2021-01-04
- Assigning CNA
- talos
- Record state
- PUBLISHED
- Severity
- Medium (CVSS 4.0)
- CNA CVSS vector
- CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Weaknesses
- CWE-908Use of Uninitialized ResourceBase
- Data version
- 5.1
- Document digest
- 0d1b88094a984290b37b05ec43882386c191de73234457fe3a4dc0750601a077
05 Affected products
06 References
- talosintelligence.comhttps://talosintelligence.com/vulnerability_reports/TALOS-2021-1243
- www.oracle.comhttps://www.oracle.com/security-alerts/cpujul2022.html
07 Fixed in
AlmaLinux 8
- bpftool Fixed in 4.18.0-372.9.1.el8
- kernel Fixed in 4.18.0-372.9.1.el8
- kernel-abi-stablelists Fixed in 4.18.0-372.9.1.el8
- kernel-core Fixed in 4.18.0-372.9.1.el8
- kernel-cross-headers Fixed in 4.18.0-372.9.1.el8
- kernel-debug Fixed in 4.18.0-372.9.1.el8
- kernel-debug-core Fixed in 4.18.0-372.9.1.el8
- kernel-debug-devel Fixed in 4.18.0-372.9.1.el8
- kernel-debug-modules Fixed in 4.18.0-372.9.1.el8
- kernel-debug-modules-extra Fixed in 4.18.0-372.9.1.el8
- kernel-devel Fixed in 4.18.0-372.9.1.el8
- kernel-doc Fixed in 4.18.0-372.9.1.el8
- kernel-headers Fixed in 4.18.0-372.9.1.el8
- kernel-modules Fixed in 4.18.0-372.9.1.el8
- kernel-modules-extra Fixed in 4.18.0-372.9.1.el8
- kernel-tools Fixed in 4.18.0-372.9.1.el8
- kernel-tools-libs Fixed in 4.18.0-372.9.1.el8
- kernel-tools-libs-devel Fixed in 4.18.0-372.9.1.el8
- perf Fixed in 4.18.0-372.9.1.el8
- python3-perf Fixed in 4.18.0-372.9.1.el8
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 8
- bpftool Fixed in 4.18.0-372.9.1.el8
- kernel Fixed in 4.18.0-372.9.1.el8
- kernel-abi-stablelists Fixed in 4.18.0-372.9.1.el8
- kernel-core Fixed in 4.18.0-372.9.1.el8
- kernel-cross-headers Fixed in 4.18.0-372.9.1.el8
- kernel-debug Fixed in 4.18.0-372.9.1.el8
- kernel-debug-core Fixed in 4.18.0-372.9.1.el8
- kernel-debug-devel Fixed in 4.18.0-372.9.1.el8
- kernel-debug-modules Fixed in 4.18.0-372.9.1.el8
- kernel-debug-modules-extra Fixed in 4.18.0-372.9.1.el8
- kernel-devel Fixed in 4.18.0-372.9.1.el8
- kernel-doc Fixed in 4.18.0-372.9.1.el8
- kernel-headers Fixed in 4.18.0-372.9.1.el8
- kernel-modules Fixed in 4.18.0-372.9.1.el8
- kernel-modules-extra Fixed in 4.18.0-372.9.1.el8
- kernel-tools Fixed in 4.18.0-372.9.1.el8
- kernel-tools-libs Fixed in 4.18.0-372.9.1.el8
- kernel-tools-libs-devel Fixed in 4.18.0-372.9.1.el8
- perf Fixed in 4.18.0-372.9.1.el8
- python3-perf Fixed in 4.18.0-372.9.1.el8
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 5.10.19-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- linux Fixed in 5.10.19-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- linux Fixed in 5.10.19-1
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 Fixed in 4.15.0-143.147
- linux-aws Fixed in 4.15.0-1102.109
- linux-aws-5.0 No fix yet
- linux-aws-5.3 No fix yet
- linux-aws-5.4 Fixed in 5.4.0-1043.45~18.04.1
- linux-azure No fix yet
- linux-azure-4.15 Fixed in 4.15.0-1114.127
- linux-azure-5.3 No fix yet
- linux-azure-5.4 Fixed in 5.4.0-1044.46~18.04.1
- linux-azure-edge No fix yet
- linux-dell300x Fixed in 4.15.0-1018.22
- linux-gcp No fix yet
- linux-gcp-4.15 Fixed in 4.15.0-1099.112
- linux-gcp-5.3 No fix yet
- linux-gcp-5.4 Fixed in 5.4.0-1041.44~18.04.1
- linux-gcp-edge No fix yet
- linux-gke-4.15 No fix yet
- linux-gke-5.4 Fixed in 5.4.0-1040.42~18.04.1
- linux-gkeop-5.4 Fixed in 5.4.0-1013.14~18.04.1
- linux-hwe No fix yet
- linux-hwe-5.4 Fixed in 5.4.0-71.79~18.04.1
- linux-hwe-edge No fix yet
- linux-kvm Fixed in 4.15.0-1091.93
- linux-oem No fix yet
- linux-oracle Fixed in 4.15.0-1071.79
- linux-oracle-5.0 No fix yet
- linux-oracle-5.3 No fix yet
- linux-oracle-5.4 Fixed in 5.4.0-1042.45~18.04.1
- linux-raspi-5.4 Fixed in 5.4.0-1033.36~18.04.1
- linux-raspi2 Fixed in 4.15.0-1085.90
- linux-snapdragon Fixed in 4.15.0-1102.111
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- linux Fixed in 5.4.0-71.79
- linux-aws Fixed in 5.4.0-1043.45
- linux-azure Fixed in 5.4.0-1044.46
- linux-gcp Fixed in 5.4.0-1041.44
- linux-gke Fixed in 5.4.0-1041.43
- linux-gkeop Fixed in 5.4.0-1013.14
- linux-hwe-5.8 Fixed in 5.8.0-53.60~20.04.1
- linux-kvm Fixed in 5.4.0-1037.38
- linux-oem-5.10 Fixed in 5.10.0-1017.18
- linux-oem-5.6 No fix yet
- linux-oracle Fixed in 5.4.0-1042.45
- linux-raspi Fixed in 5.4.0-1033.36
- linux-raspi2 No fix yet
- linux-riscv No fix yet
- linux-riscv-5.8 Fixed in 5.8.0-25.27~20.04.1
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- linux-intel-iot-realtime No fix yet
- linux-realtime No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- linux-raspi-realtime No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 14.04 LTS
- linux No fix yet
- linux-aws No fix yet
- linux-azure Fixed in 4.15.0-1114.127~14.04.1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
- linux-lts-xenial No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- linux No fix yet
- linux-aws No fix yet
- linux-aws-hwe Fixed in 4.15.0-1102.109~16.04.1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
- linux-azure Fixed in 4.15.0-1114.127~16.04.1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
- linux-gcp Fixed in 4.15.0-1099.112~16.04.1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
- linux-hwe Fixed in 4.15.0-143.147~16.04.3Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
- linux-kvm No fix yet
- linux-oracle Fixed in 4.15.0-1071.79~16.04.1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS-updates 16.04 LTS
- linux-fips No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS-updates 18.04 LTS
- linux-aws-fips Fixed in 4.15.0-2044.46Available with Ubuntu Pro: https://ubuntu.com/pro
- linux-azure-fips Fixed in 4.15.0-2026.29Available with Ubuntu Pro: https://ubuntu.com/pro
- linux-fips Fixed in 4.15.0-1059.67Available with Ubuntu Pro: https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS-updates 20.04 LTS
- linux-aws-fips Fixed in 5.4.0-1069.73+fips2Available with Ubuntu Pro: https://ubuntu.com/pro
- linux-azure-fips Fixed in 5.4.0-1073.76+fips1Available with Ubuntu Pro: https://ubuntu.com/pro
- linux-gcp-fips Fixed in 5.4.0-1067.71~20.04.1Available with Ubuntu Pro: https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS 16.04 LTS
- linux-fips No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS 18.04 LTS
- linux-aws-fips No fix yet
- linux-azure-fips No fix yet
- linux-fips No fix yet
- linux-gcp-fips No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro FIPS 20.04 LTS
- linux-aws-fips No fix yet
- linux-azure-fips No fix yet
- linux-gcp-fips 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.