Skip to content
Noroxi
CVE-2021-0920· NVD / CVE Program· CNA google_android

In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition.

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

MediumCVSS 6.4 · v3.1KEVWeaponized Fix available
Published
Dec 15, 2021
Updated
Jun 16, 2026
EPSS
0.8% · 56th percentile
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

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 government agencies: Jun 13, 2022.

Affected systems

VendorProduct
linuxlinux kernel
googleandroid
debiandebian linux

Affected versions

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

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

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 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-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 4.12.14-197.105.14.12.14-197.105.1
openSUSE:Leap 15.3kernel-kvmsmallbefore 5.3.18-150300.59.60.45.3.18-150300.59.60.4
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

Other highest-scoring records for the same primary product.

  • 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
  • CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV
    83Now
  • CVE-2019-13272In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to creKEV
    77This week
  • CVE-2013-6282The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the v6k and v7 ARM platforms do not validate certain addKEV
    77This week
  • CVE-2013-2094The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, which allows loKEV
    77This week

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. TodaySep 29, 2026+1749 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

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

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.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

All records