BlackTreeCVE Intelligence
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Full vulnerability report · 2019
CVE-2019-6974High confidence

In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free

Unknown · Unknown

8.1HighCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

High technical severity with public exploit material referenced by a structured source; 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:Critical, raised one band.upgradedsince 4 Aug 2024

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 16.52% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Unknown Unknown 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: Within 3 daysRemediation target: Within 90 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.4.19.20-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.4.19.20-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.4.19.20-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.4.19.20-1Debian 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
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-2019-16527

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 with public exploit material referenced by a structured source; 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

In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free.

What

In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free.

Why

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free.

Why

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
a network path → Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
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-362 ↗

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition'). The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/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.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing 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
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-362Public exploit reference
A

Official authority intelligence

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

CERT-FR · French · CERTFR-2020-AVI-030Multiples vulnérabilités dans le noyau Linux de Red Hat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Red Hat. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-592Multiples vulnérabilités dans le noyau Linux de Red Hat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Red Hat. Elles permettent à un attaquant de provoquer un déni de service à distance, une atteinte à la confidentialité des données et une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-574Multiples vulnérabilités dans F5 BIG-IP

De multiples vulnérabilités ont été découvertes dans F5 BIG-IP. Elles permettent à un attaquant de provoquer un déni de service à distance, un contournement de la politique de sécurité et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-451Multiples vulnérabilités dans le noyau Linux de Red Hat

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

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-299Multiples vulnérabilités dans IBM QRadar

cve.org/CVERecord?id=CVE-2018-17972 Référence CVE CVE-2018-5344 https://www.cve.org/CVERecord?id=CVE-2018-5344 Référence CVE CVE-2018-7740 https://www.cve.org/CVERecord?id=CVE-2018-7740 Référence CVE CVE-2018-9568 https://www.cve.org/CVERecord?id=CVE-2018-9568 Référence CVE CVE-2019-3855 https://www.cve.org/CVERecord?id=CVE-2019-3855 Référence CVE CVE-2019-3856 https://www.cve.org/CVERecord?id=CVE-2019-3856 Référence CVE CVE-2019-3857 https://www.cve.org/CVERecord?id=CVE-2019-3857 Référence CVE CVE-2019-3863 https://www.cve.org/CVERecord?id=CVE-2019-3863 Référence CVE CVE-2019-5953 https://www.cve.org/CVERecord?id=CVE-2019-5953 Référence CVE CVE-2019-6974 https://www.cve.org/CVERecord?id=CVE-2019-6974 Référence CVE CVE-2019-7221 https://www.cve.org/CVERecord?id=CVE-2019-7221 Gestion détaillée du document le 28 juin 2019 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-233Multiples vulnérabilités dans le noyau Linux de SUSE

org/CVERecord?id=CVE-2018-20169 Référence CVE CVE-2018-5391 https://www.cve.org/CVERecord?id=CVE-2018-5391 Référence CVE CVE-2018-9516 https://www.cve.org/CVERecord?id=CVE-2018-9516 Référence CVE CVE-2018-9568 https://www.cve.org/CVERecord?id=CVE-2018-9568 Référence CVE CVE-2019-11091 https://www.cve.org/CVERecord?id=CVE-2019-11091 Référence CVE CVE-2019-11486 https://www.cve.org/CVERecord?id=CVE-2019-11486 Référence CVE CVE-2019-3459 https://www.cve.org/CVERecord?id=CVE-2019-3459 Référence CVE CVE-2019-3460 https://www.cve.org/CVERecord?id=CVE-2019-3460 Référence CVE CVE-2019-3882 https://www.cve.org/CVERecord?id=CVE-2019-3882 Référence CVE CVE-2019-6974 https://www.cve.org/CVERecord?id=CVE-2019-6974 Référence CVE CVE-2019-7221 https://www.cve.org/CVERecord?id=CVE-2019-7221 Référence CVE CVE-2019-7222 https://www.cve.org/CVERecord?id=CVE-2019-7222 Référence CVE CVE-2019-8564 https://www.cve.org/CVERecord?id=CVE-2019-8564 Référence CVE CVE-2019-9213 https://www.cve.org/CVERecord?id=CVE-2019-9213 Référence CVE CVE-2019-9503 https://www.cve.org/CVERecord?id=CVE-2019-9503 Gestion détaillée du document le 20 mai 2019 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-183Multiples vulnérabilités dans le noyau Linux de RedHat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de RedHat. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-145Multiples vulnérabilités dans le noyau Linux d'Ubuntu

g/CVERecord?id=CVE-2018-14678 Référence CVE CVE-2018-16884 https://www.cve.org/CVERecord?id=CVE-2018-16884 Référence CVE CVE-2018-18021 https://www.cve.org/CVERecord?id=CVE-2018-18021 Référence CVE CVE-2018-19824 https://www.cve.org/CVERecord?id=CVE-2018-19824 Référence CVE CVE-2018-9517 https://www.cve.org/CVERecord?id=CVE-2018-9517 Référence CVE CVE-2019-3459 https://www.cve.org/CVERecord?id=CVE-2019-3459 Référence CVE CVE-2019-3460 https://www.cve.org/CVERecord?id=CVE-2019-3460 Référence CVE CVE-2019-3701 https://www.cve.org/CVERecord?id=CVE-2019-3701 Référence CVE CVE-2019-3819 https://www.cve.org/CVERecord?id=CVE-2019-3819 Référence CVE CVE-2019-6974 https://www.cve.org/CVERecord?id=CVE-2019-6974 Référence CVE CVE-2019-7221 https://www.cve.org/CVERecord?id=CVE-2019-7221 Référence CVE CVE-2019-7222 https://www.cve.org/CVERecord?id=CVE-2019-7222 Référence CVE CVE-2019-7308 https://www.cve.org/CVERecord?id=CVE-2019-7308 Référence CVE CVE-2019-8912 https://www.cve.org/CVERecord?id=CVE-2019-8912 Référence CVE CVE-2019-8956 https://www.cve.org/CVERecord?id=CVE-2019-8956 Référence CVE CVE-2019-8980 https://www.cve.org/CVERecord?id=CVE-2019-8980 Référence CVE CVE-2019-9003 https://www.cve.org/CVERecord?id=CVE-2019-9003 Référence CVE CVE-2019-9162 https://www.cve.org/CVERecord?id=CVE-2019-9162 Ré

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-144Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Elles permettent à un attaquant de provoquer

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-131Multiples 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 problème de sécurité non spécifié par l'éditeur, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-127Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-123Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2019-AVI-121Multiples 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 problème de sécurité non spécifié par l'éditeur, un déni de service à distance et un déni de service.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2019-002787Linux Kernel における解放済みメモリの使用に関する脆弱性

Linux Kernel には、解放済みメモリの使用に関する脆弱性が存在します。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2019-001392Linux kernel における競合状態に関する脆弱性

Linux kernel には、競合状態に関する脆弱性、解放済みメモリの使用に関する脆弱性が存在します。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2019-002849Linux Kernel における脆弱性

Linux Kernel には、不特定の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
n/a
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. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 15 Feb 2019 · Last source change 4 Aug 2024, 20:38 UTC · CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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 2026-09-01
European sourceENISA EUVD · EUVD-2019-16527
Product sourceUnavailable
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
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 ↗
  1. ENISA EUVD mappingEUVD-2019-16527 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2019-16527"}
    ENISA EUVD ↗
  2. Vendor guidanceAuthoritative vendor guidance changed: added patch: bugs.chromium.org/detail?id=1765; added patch: git.kernel.org/commit?id=cfa39381173d5f969daf43582c95ad679189cbc9; removed vendor advisory: access.redhat.com/RHBA-2019:0959; removed vendor advisory: access.redhat.com/RHSA-2019:0818; 6 further additions; 12 further removals.
    Before
    vendor advisory: access.redhat.com/RHBA-2019:0959 · vendor advisory: access.redhat.com/RHSA-2019:0818 · vendor advisory: access.redhat.com/RHSA-2019:0833 · 11 more references
    After
    patch: bugs.chromium.org/detail?id=1765 · patch: git.kernel.org/commit?id=cfa39381173d5f969daf43582c95ad679189cbc9 · patch: github.com/cfa39381173d5f969daf43582c95ad679189cbc9 · 5 more references
    bugs.chromium.org ↗
  3. Affected versionsThe structured affected or fixed version information changed.
    Before
    n/a · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    n/a · 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.
    CNA ↗
  4. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    bugs.chromium.org ↗
  5. Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.
    Before
    Public exploit reference
    After
    Public exploit reference
    bugs.chromium.org ↗
  6. SeveritySeverity changed from Unknown to High.
    Before
    Unknown
    After
    High
    NIST NVD ↗
  7. CVSS scoreCVSS score changed from not recorded to 8.1 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
    Before
    not recorded
    After
    8.1 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)
    NIST NVD ↗
  8. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
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-2019-6974 · cve.blacktree.nl