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NVD / CVE Program· CNA google_android

CVE-2021-0920: In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition.

MediumCVSS 6.4 · v3.1KEVWeaponized Fix available

Noroxi assessment

Priority: Plan (action score 55/100)

  • CISA has confirmed exploitation in the wild (May 23, 2022). Remediation deadline for US federal agencies: Jun 13, 2022.
  • Probability of exploitation in the next 30 days: 0.86% (FIRST EPSS); higher than 59.2% of all records.
  • Someone with local access to the system can trigger it. Administrator privileges are required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: kernel-tools-libs-devel (AlmaLinux:8) 4.18.0-348.20.1.el8_5; linux (Debian:12) 5.14.6-1; linux (Debian:9) 4.9.290-1.
  • Mentioned 4 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Add it to your regular patch cycle. Upgrade to kernel-tools-libs-devel (AlmaLinux:8) 4.18.0-348.20.1.el8_5; linux (Debian:12) 5.14.6-1; linux (Debian:9) 4.9.290-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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

Published
Dec 15, 2021
Updated
Jun 16, 2026
EPSS
0.8% · 59th percentile

Report tools

JSON

Action score

55

Plan

Add it to your regular patch cycle.

CVSS
25 / 40 · 6.4 / 10
CISA KEV
30 / 30 · Listed
EPSS
0 / 30 · 0.8%

CISA SSVC decision

Exploitation
active
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on May 23, 2022. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Jun 13, 2022.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel
googleandroid
debiandebian linux

Versions reported by the vendor

Affected version ranges reported by the assigning authority (google_android). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a Android

    • Android kernelaffected
Affected versions · NVD (4)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux9.0
  • google androidall versions
  • linux linux kernelup to 5.13 inclusive
  • linux linux kernel5.14

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8kernel-tools-libs-develbefore 4.18.0-348.20.1.el8_54.18.0-348.20.1.el8_5
Debian:12linuxbefore 5.14.6-15.14.6-1
Debian:9linuxbefore 4.9.290-14.9.290-1
openSUSE:Leap 15.3dtb-aarch64before 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-64kbbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-azurebefore 5.3.18-150300.38.50.15.3.18-150300.38.50.1
openSUSE:Leap 15.3kernel-debugbefore 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-debugbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-defaultbefore 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-defaultbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-default-basebefore 5.3.18-150300.59.60.4.150300.18.37.55.3.18-150300.59.60.4.150300.18.37.5
openSUSE:Leap 15.3kernel-docsbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-kvmsmallbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-kvmsmallbefore 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-obs-buildbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-obs-qabefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-preemptbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-sourcebefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-source-azurebefore 5.3.18-150300.38.50.15.3.18-150300.38.50.1
openSUSE:Leap 15.3kernel-symsbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
openSUSE:Leap 15.3kernel-syms-azurebefore 5.3.18-150300.38.50.15.3.18-150300.38.50.1
openSUSE:Leap 15.3kernel-vanillabefore 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-zfcpdumpbefore 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-zfcpdumpbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2021-43975Nov 17, 2021 · In the Linux kernel through 5.15.2, hw_atl_utils_fw_rpc_wait in drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c allows an…
    26Monitor
  • ← EarlierCVE-2018-25020Dec 8, 2021 · The BPF subsystem in the Linux kernel before 4.17 mishandles situations with a long jump over an instruction sequence where inner…
    31Monitor
  • Later →CVE-2021-45095Dec 16, 2021 · pep_sock_accept in net/phonet/pep.c in the Linux kernel through 5.15.8 has a refcount leak.
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
almalinux:kernel-tools-libs-devel4.18.0-348.20.1.el8_5 · AlmaLinux:8Package registry (OSV)
debian:linux5.14.6-1 · Debian:12Package registry (OSV)
opensuse:dtb-aarch645.3.18-150300.59.60.4 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-64kb5.3.18-150300.59.60.4 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-azure5.3.18-150300.38.50.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-debug4.12.14-197.105.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-default4.12.14-197.105.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-default-base5.3.18-150300.59.60.4.150300.18.37.5 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-docs5.3.18-150300.59.60.4 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-kvmsmall4.12.14-197.105.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-source-azure5.3.18-150300.38.50.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-syms-azure5.3.18-150300.38.50.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-vanilla4.12.14-197.105.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-zfcpdump4.12.14-197.105.1 · openSUSE:Leap 15.3Package registry (OSV)
red hat:kpatch-patch-4_18_0-193_46_10:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_46_1-debuginfo0:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_46_1-debugsource0:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_47_10:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_47_1-debuginfo0:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_47_1-debugsource0:1-9.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_51_10:1-6.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_51_1-debuginfo0:1-6.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_51_1-debugsource0:1-6.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_56_10:1-5.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_56_1-debuginfo0:1-5.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
red hat:kpatch-patch-4_18_0-193_56_1-debugsource0:1-5.el8_2 · Red Hat:rhel_eus:8.2::baseosPackage registry (OSV)
rocky linux:kernel0:4.18.0-348.20.1.el8_5 · Rocky Linux:8Package registry (OSV)
rocky linux:kernel-rt0:4.18.0-348.20.1.rt7.150.el8_5 · Rocky Linux:8Package registry (OSV)
suse:kernel-azure4.12.14-16.85.1 · SUSE:Linux Enterprise Server 12 SP5Package registry (OSV)
suse:kernel-default4.12.14-122.106.1 · SUSE:Linux Enterprise High Availability Extension 12 SP5Package registry (OSV)

+10

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. CISA KEV+158 d
  3. TodayNov 14, 2026+1794 d

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
High
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records