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.
Published severityHigh→Operational 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
Confirm that the asset runs Unknown Unknown and falls inside the recorded affected range.
Verify the installed build against the product-specific fixed version after deployment.
Validate exposure, authentication requirements and compensating controls in the actual environment.
Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
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.
Canonical Ubuntu Security: 1 affected package state with no published fix
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 release
Source package
Vendor state
Fixed version
Evidence
Debian trixietrixie · source
linux
Vendor fix publishedDebian records a fixed source-package version for this release.
Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.
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: 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.
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2019-16527Official EUVD mapping
0 linked advisory records.
Official EUVD record ↗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
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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
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
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
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.
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.
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.
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.