BlackTreeCVE Intelligence
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Full vulnerability report · 2021
CVE-2021-3612High confidence

An out-of-bounds memory write flaw was found in the Linux kernel's joystick devices subsystem in versions before 5.9-rc1, in the way the user calls ioctl JSIOCSBTNMAP

Unknown · kernel

7.8HighCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Medium, lowered one band.downgradedsince 3 Aug 2024

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.69% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown kernel and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

5 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 1 affected package state shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.46-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.46-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.46-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.46-3Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2021-3612 · CSAF 2.0 · revision 41 · interimSUSE Product Security TeamCVE-2021-3612
15 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • SLES 15 SP1 CHOST Images for Amazon EC2
  • SLES 15 SP2 CHOST Images for Amazon EC2
  • SLES 15 SP3 CHOST Images for Amazon EC2
  • SLES 15 SP4 CHOST Images for Amazon EC2
  • SLES 15 SP5 CHOST Images for Amazon EC2
  • SLES 15 SP1 CHOST Images for Google
  • SLES 15 SP2 CHOST Images for Google
  • SLES 15 SP3 CHOST Images for Google
  • SLES 15 SP4 CHOST Images for Google
  • SLES 15 SP5 CHOST Images for Google
  • SLES 15 SP1 CHOST Images for Microsoft Azure
  • SLES 15 SP2 CHOST Images for Microsoft Azure
Summary
An out-of-bounds memory write flaw was found in the Linux kernel's joystick devices subsystem in versions before 5.9-rc1, in the way the user calls ioctl JSIOCSBTNMAP. This flaw allows a local user to crash the system or possibly escalate their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-26916

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

An out-of-bounds memory write flaw was found in the Linux kernel's joystick devices subsystem in versions before 5.9-rc1, in the way the user calls ioctl JSIOCSBTNMAP. This flaw allows a local user to crash the system or possibly escalate their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

What

An out-of-bounds memory write flaw was found in the Linux kernel's joystick devices subsystem in versions before 5.9-rc1, in the way the user calls ioctl JSIOCSBTNMAP. This flaw allows a local user to crash the system or possibly escalate their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Why

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

An out-of-bounds memory write flaw was found in the Linux kernel's joystick devices subsystem in versions before 5.9-rc1, in the way the user calls ioctl JSIOCSBTNMAP. This flaw allows a local user to crash the system or possibly escalate their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Why

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → Improper Input Validation → disrupt the affected service
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-20 ↗

CWE-20: Improper Input Validation. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
Denial of serviceCWE-20
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

Cyber Security Agency of Singapore · English · CSA-SB-20210714Security Bulletin 14 Jul 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 14 Jul 2021, published on 14 July 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-265Multiples vulnérabilités dans le noyau Linux de Ubuntu

CVERecord?id=CVE-2021-32399 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-33098 https://www.cve.org/CVERecord?id=CVE-2021-33098 Référence CVE CVE-2021-34693 https://www.cve.org/CVERecord?id=CVE-2021-34693 Référence CVE CVE-2021-3483 https://www.cve.org/CVERecord?id=CVE-2021-3483 Référence CVE CVE-2021-3506 https://www.cve.org/CVERecord?id=CVE-2021-3506 Référence CVE CVE-2021-3564 https://www.cve.org/CVERecord?id=CVE-2021-3564 Référence CVE CVE-2021-3573 https://www.cve.org/CVERecord?id=CVE-2021-3573 Référence CVE CVE-2021-3612 https://www.cve.org/CVERecord?id=CVE-2021-3612 Référence CVE CVE-2021-3679 https://www.cve.org/CVERecord?id=CVE-2021-3679 Référence CVE CVE-2021-38160 https://www.cve.org/CVERecord?id=CVE-2021-38160 Référence CVE CVE-2021-38198 https://www.cve.org/CVERecord?id=CVE-2021-38198 Référence CVE CVE-2021-38204 https://www.cve.org/CVERecord?id=CVE-2021-38204 Référence CVE CVE-2021-38208 https://www.cve.org/CVERecord?id=CVE-2021-38208 Référence CVE CVE-2021-39648 https://www.cve.org/CVERecord?id=CVE-2021-39648 Référence CVE CVE-2021-39685 https://www.cve.org/CVERecord?id=CVE-2021-39685 Référence CVE CVE-2021-39698 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-176Multiples vulnérabilités dans le noyau Linux d'Ubuntu

ecord?id=CVE-2021-28712 Référence CVE CVE-2021-28713 https://www.cve.org/CVERecord?id=CVE-2021-28713 Référence CVE CVE-2021-28714 https://www.cve.org/CVERecord?id=CVE-2021-28714 Référence CVE CVE-2021-28715 https://www.cve.org/CVERecord?id=CVE-2021-28715 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-34693 https://www.cve.org/CVERecord?id=CVE-2021-34693 Référence CVE CVE-2021-3483 https://www.cve.org/CVERecord?id=CVE-2021-3483 Référence CVE CVE-2021-3564 https://www.cve.org/CVERecord?id=CVE-2021-3564 Référence CVE CVE-2021-3612 https://www.cve.org/CVERecord?id=CVE-2021-3612 Référence CVE CVE-2021-3679 https://www.cve.org/CVERecord?id=CVE-2021-3679 Référence CVE CVE-2021-38204 https://www.cve.org/CVERecord?id=CVE-2021-38204 Référence CVE CVE-2021-39685 https://www.cve.org/CVERecord?id=CVE-2021-39685 Référence CVE CVE-2021-4083 https://www.cve.org/CVERecord?id=CVE-2021-4083 Référence CVE CVE-2021-4155 https://www.cve.org/CVERecord?id=CVE-2021-4155 Référence CVE CVE-2021-42008 https://www.cve.org/CVERecord?id=CVE-2021-42008 Référence CVE CVE-2021-4202 https://www.cve.org/CVERecord?id=CVE-2021-4202 Référence CVE CVE-2021-43975 https://www.cve.org/CVERecord?id=CVE-2021-

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-969Multiples vulnérabilités dans le noyau Linux de Debian

1] Page de suivi des vulnérabilités https://security-tracker.debian.org/tracker/source-package/linux Référence CVE CVE-2020-16119 https://www.cve.org/CVERecord?id=CVE-2020-16119 Référence CVE CVE-2020-3702 https://www.cve.org/CVERecord?id=CVE-2020-3702 Référence CVE CVE-2021-0920 https://www.cve.org/CVERecord?id=CVE-2021-0920 Référence CVE CVE-2021-20317 https://www.cve.org/CVERecord?id=CVE-2021-20317 Référence CVE CVE-2021-20321 https://www.cve.org/CVERecord?id=CVE-2021-20321 Référence CVE CVE-2021-20322 https://www.cve.org/CVERecord?id=CVE-2021-20322 Référence CVE CVE-2021-22543 https://www.cve.org/CVERecord?id=CVE-2021-22543 Référence CVE CVE-2021-3612 https://www.cve.org/CVERecord?id=CVE-2021-3612 Référence CVE CVE-2021-3653 https://www.cve.org/CVERecord?id=CVE-2021-3653 Référence CVE CVE-2021-3655 https://www.cve.org/CVERecord?id=CVE-2021-3655 Référence CVE CVE-2021-3679 https://www.cve.org/CVERecord?id=CVE-2021-3679 Référence CVE CVE-2021-37159 https://www.cve.org/CVERecord?id=CVE-2021-37159 Référence CVE CVE-2021-3732 https://www.cve.org/CVERecord?id=CVE-2021-3732 Référence CVE CVE-2021-3753 https://www.cve.org/CVERecord?id=CVE-2021-3753 Référence CVE CVE-2021-3760 https://www.cve.org/CVERecord?id=CVE-2021-3760 Référence CVE CVE-2021-3816 https://www.cve.org/CVERecord?id=CVE-2021-3816

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-742Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-726Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-717Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu . Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-695Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-629Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-602Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-595Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-563Multiples vulnérabilités dans le noyau Linux de SUSE

ERecord?id=CVE-2021-33034 Référence CVE CVE-2021-33200 https://www.cve.org/CVERecord?id=CVE-2021-33200 Référence CVE CVE-2021-33624 https://www.cve.org/CVERecord?id=CVE-2021-33624 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-34693 https://www.cve.org/CVERecord?id=CVE-2021-34693 Référence CVE CVE-2021-3491 https://www.cve.org/CVERecord?id=CVE-2021-3491 Référence CVE CVE-2021-35039 https://www.cve.org/CVERecord?id=CVE-2021-35039 Référence CVE CVE-2021-3573 https://www.cve.org/CVERecord?id=CVE-2021-3573 Référence CVE CVE-2021-3609 https://www.cve.org/CVERecord?id=CVE-2021-3609 Référence CVE CVE-2021-3612 https://www.cve.org/CVERecord?id=CVE-2021-3612 Référence CVE CVE-2020-24586 https://www.cve.org/CVERecord?id=CVE-2020-24586 Référence CVE CVE-2020-24587 https://www.cve.org/CVERecord?id=CVE-2020-24587 Référence CVE CVE-2020-24588 https://www.cve.org/CVERecord?id=CVE-2020-24588 Référence CVE CVE-2020-26139 https://www.cve.org/CVERecord?id=CVE-2020-26139 Référence CVE CVE-2020-26141 https://www.cve.org/CVERecord?id=CVE-2020-26141 Référence CVE CVE-2020-26145 https://www.cve.org/CVERecord?id=CVE-2020-26145 Référence CVE CVE-2020-26147 https://www.cve.org/CVERecord?id=CVE-2020-26147 Référence CVE CVE-2020-26558 https://www.cve.org/CVERecord?id=C

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-550Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-009121Linux Kernel の joystick devices subsystem における境界外書き込みに関する脆弱性

Linux Kernel の joystick devices subsystem には、境界外書き込みに関する脆弱性が存在します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 9 Jul 2021 · Last source change 3 Aug 2024, 17:01 UTC · CWE-20 · Improper Input Validation

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-26916
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-26916↗Vendor CSAF · SUSE Product Security Team↗Patch or update reference↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-3612 · cve.blacktree.nl