CVE-2021-0920 Android Kernel Race Condition
Exploited in the wild
Medium 6.4
Published
Updated
Check this codebase for CVE-2021-0920 and fix it if it is affected.
What it is: CVE-2021-0920 is a medium-severity use after free vulnerability in Debian Debian Linux, published on 15 Dec 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2021-0920 in the wild since at least 23 May 2022.
Affected product: Debian Debian Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2021-0920/ (Markdown: https://insights.sbomify.com/CVE-2021-0920/index.md)
A race condition in the Android kernel's unix socket handling allows local attackers to escalate privileges to system level.
- Exploited in the wild
- Since 23 May 2022
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-0920?
CVE-2021-0920 is a medium-severity use after free vulnerability in Debian Debian Linux, published on 15 Dec 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-196926917References: Upstream kernel
Which versions are affected by CVE-2021-0920?
It affects 3 products.
Linux distribution packages (34)
kgraft-patch-SLE12-SP4_Update_19 SUSE:Linux Enterprise Live Patching 12 SP4 | All versions | 15-2.2 |
kgraft-patch-SLE12-SP4_Update_20 SUSE:Linux Enterprise Live Patching 12 SP4 | All versions | 12-2.1 |
kgraft-patch-SLE12-SP4_Update_21 SUSE:Linux Enterprise Live Patching 12 SP4 | All versions | 11-2.1 |
kgraft-patch-SLE12-SP4_Update_22 SUSE:Linux Enterprise Live Patching 12 SP4 | All versions | 9-2.1 |
kgraft-patch-SLE12-SP4_Update_23 SUSE:Linux Enterprise Live Patching 12 SP4 | All versions | 4-2.1 |
kgraft-patch-SLE12-SP5_Update_16 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 15-2.2 |
kgraft-patch-SLE12-SP5_Update_17 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 13-2.1 |
kgraft-patch-SLE12-SP5_Update_18 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 12-2.1 |
kgraft-patch-SLE12-SP5_Update_19 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 10-2.1 |
kgraft-patch-SLE12-SP5_Update_20 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 10-2.1 |
kgraft-patch-SLE12-SP5_Update_21 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 9-2.1 |
kgraft-patch-SLE12-SP5_Update_22 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 8-2.1 |
kgraft-patch-SLE12-SP5_Update_23 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 6-2.1 |
kgraft-patch-SLE12-SP5_Update_24 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 6-2.1 |
kgraft-patch-SLE12-SP5_Update_25 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 4-2.1 |
kgraft-patch-SLE12-SP5_Update_26 SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 4-2.1 |
kernel-livepatch-SLE15_Update_23 SUSE:Linux Enterprise Live Patching 15 | All versions | 15-2.2 |
kernel-livepatch-SLE15_Update_24 SUSE:Linux Enterprise Live Patching 15 | All versions | 12-2.1 |
kernel-livepatch-SLE15_Update_25 SUSE:Linux Enterprise Live Patching 15 | All versions | 9-2.1 |
kernel-livepatch-SLE15_Update_26 SUSE:Linux Enterprise Live Patching 15 | All versions | 4-2.1 |
kernel-livepatch-SLE15-SP1_Update_23 SUSE:Linux Enterprise Live Patching 15 SP1 | All versions | 15-2.2 |
kernel-livepatch-SLE15-SP1_Update_24 SUSE:Linux Enterprise Live Patching 15 SP1 | All versions | 12-2.1 |
kernel-livepatch-SLE15-SP1_Update_25 SUSE:Linux Enterprise Live Patching 15 SP1 | All versions | 11-2.1 |
kernel-livepatch-SLE15-SP1_Update_26 SUSE:Linux Enterprise Live Patching 15 SP1 | All versions | 9-2.1 |
kernel-livepatch-SLE15-SP1_Update_27 SUSE:Linux Enterprise Live Patching 15 SP1 | All versions | 4-2.1 |
kernel-livepatch-SLE15-SP2_Update_25 SUSE:Linux Enterprise Live Patching 15 SP2 | All versions | 2-150200.2.1 |
kgraft-patch-SLE12-SP3_Update_38 SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 15-2.2 |
kgraft-patch-SLE12-SP3_Update_39 SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 12-2.1 |
kgraft-patch-SLE12-SP3_Update_40 SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 9-2.1 |
kgraft-patch-SLE12-SP3_Update_41 SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 5-2.1 |
kgraft-patch-SLE12-SP3_Update_38 SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 15-2.2 |
kgraft-patch-SLE12-SP3_Update_39 SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 12-2.1 |
kgraft-patch-SLE12-SP3_Update_40 SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 9-2.1 |
kgraft-patch-SLE12-SP3_Update_41 SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 5-2.1 |
Products include Debian Debian Linux, Google Android, Linux kernel.
How do I fix CVE-2021-0920?
Apply the vendor's patch. US federal agencies must fix it by 13 Jun 2022.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-0920 being exploited?
Yes. Attackers have exploited CVE-2021-0920 in the wild since at least 23 May 2022.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as A-196926917, ASB-A-196926917, DEBIAN-CVE-2021-0920, GHSA-r93f-j2vf-vmc4, SUSE-SU-2022:0647-1, SUSE-SU-2022:0667-1 and 2 more.